diff --git a/powerdnsadmin/default_config.py b/powerdnsadmin/default_config.py
index 7b82935..ce09bcc 100644
--- a/powerdnsadmin/default_config.py
+++ b/powerdnsadmin/default_config.py
@@ -16,12 +16,12 @@ SQLA_DB_HOST = '127.0.0.1'
 SQLA_DB_NAME = 'pda'
 SQLALCHEMY_TRACK_MODIFICATIONS = True
 
-### DATBASE - MySQL
+### DATABASE - MySQL
 SQLALCHEMY_DATABASE_URI = 'mysql://'+SQLA_DB_USER+':'+SQLA_DB_PASSWORD+'@'+SQLA_DB_HOST+'/'+SQLA_DB_NAME
 
-### DATABSE - SQLite
+### DATABASE - SQLite
 # SQLALCHEMY_DATABASE_URI = 'sqlite:///' + os.path.join(basedir, 'pdns.db')
 
 # SAML Authnetication
 SAML_ENABLED = False
-SAML_ASSERTION_ENCRYPTED = True
\ No newline at end of file
+SAML_ASSERTION_ENCRYPTED = True
diff --git a/powerdnsadmin/lib/utils.py b/powerdnsadmin/lib/utils.py
index 82e6b6b..43c7617 100644
--- a/powerdnsadmin/lib/utils.py
+++ b/powerdnsadmin/lib/utils.py
@@ -221,6 +221,7 @@ def ensure_list(l):
 
     yield from l
 
+
 class customBoxes:
     boxes = {
         "reverse": (" ", " "),
diff --git a/powerdnsadmin/models/account_user.py b/powerdnsadmin/models/account_user.py
index a582884..81bb43a 100644
--- a/powerdnsadmin/models/account_user.py
+++ b/powerdnsadmin/models/account_user.py
@@ -14,4 +14,4 @@ class AccountUser(db.Model):
         self.user_id = user_id
 
     def __repr__(self):
-        return '<Account_User {0} {1}>'.format(self.account_id, self.user_id)
\ No newline at end of file
+        return '<Account_User {0} {1}>'.format(self.account_id, self.user_id)
diff --git a/powerdnsadmin/models/api_key.py b/powerdnsadmin/models/api_key.py
index 52602c0..9c7d9d3 100644
--- a/powerdnsadmin/models/api_key.py
+++ b/powerdnsadmin/models/api_key.py
@@ -91,9 +91,9 @@ class ApiKey(db.Model):
                              current_app.config.get('SALT').encode('utf-8'))
 
     def check_password(self, hashed_password):
-        # Check hased password. Using bcrypt,
+        # Check hashed password. Using bcrypt,
         # the salt is saved into the hash itself
-        if (self.plain_text_password):
+        if self.plain_text_password:
             return bcrypt.checkpw(self.plain_text_password.encode('utf-8'),
                                   hashed_password.encode('utf-8'))
         return False
diff --git a/powerdnsadmin/models/domain.py b/powerdnsadmin/models/domain.py
index d17d31c..40453b5 100644
--- a/powerdnsadmin/models/domain.py
+++ b/powerdnsadmin/models/domain.py
@@ -74,23 +74,21 @@ class Domain(db.Model):
         """
         Get all domains which has in PowerDNS
         """
-        headers = {}
-        headers['X-API-Key'] = self.PDNS_API_KEY
+        headers = {'X-API-Key': self.PDNS_API_KEY}
         jdata = utils.fetch_json(urljoin(
             self.PDNS_STATS_URL, self.API_EXTENDED_URL +
-            '/servers/localhost/zones/{0}'.format(domain_name)),
-                                 headers=headers,
-                                 timeout=int(
-                                     Setting().get('pdns_api_timeout')),
-                                 verify=Setting().get('verify_ssl_connections'))
+                                 '/servers/localhost/zones/{0}'.format(domain_name)),
+            headers=headers,
+            timeout=int(
+                Setting().get('pdns_api_timeout')),
+            verify=Setting().get('verify_ssl_connections'))
         return jdata
 
     def get_domains(self):
         """
         Get all domains which has in PowerDNS
         """
-        headers = {}
-        headers['X-API-Key'] = self.PDNS_API_KEY
+        headers = {'X-API-Key': self.PDNS_API_KEY}
         jdata = utils.fetch_json(
             urljoin(self.PDNS_STATS_URL,
                     self.API_EXTENDED_URL + '/servers/localhost/zones'),
@@ -120,8 +118,7 @@ class Domain(db.Model):
         dict_db_domain = dict((x.name, x) for x in db_domain)
         current_app.logger.info("Found {} entries in PowerDNS-Admin".format(
             len(list_db_domain)))
-        headers = {}
-        headers['X-API-Key'] = self.PDNS_API_KEY
+        headers = {'X-API-Key': self.PDNS_API_KEY}
         try:
             jdata = utils.fetch_json(
                 urljoin(self.PDNS_STATS_URL,
@@ -211,8 +208,7 @@ class Domain(db.Model):
         Add a domain to power dns
         """
 
-        headers = {}
-        headers['X-API-Key'] = self.PDNS_API_KEY
+        headers = {'X-API-Key': self.PDNS_API_KEY}
 
         domain_name = domain_name + '.'
         domain_ns = [ns + '.' for ns in domain_ns]
@@ -262,15 +258,14 @@ class Domain(db.Model):
         """
         Read Domain from PowerDNS and add into PDNS-Admin
         """
-        headers = {}
-        headers['X-API-Key'] = self.PDNS_API_KEY
+        headers = {'X-API-Key': self.PDNS_API_KEY}
         if not domain:
             try:
                 domain = utils.fetch_json(
                     urljoin(
                         self.PDNS_STATS_URL, self.API_EXTENDED_URL +
-                        '/servers/localhost/zones/{0}'.format(
-                            domain_dict['name'])),
+                                             '/servers/localhost/zones/{0}'.format(
+                                                 domain_dict['name'])),
                     headers=headers,
                     timeout=int(Setting().get('pdns_api_timeout')),
                     verify=Setting().get('verify_ssl_connections'))
@@ -315,8 +310,8 @@ class Domain(db.Model):
         domain = Domain.query.filter(Domain.name == domain_name).first()
         if not domain:
             return {'status': 'error', 'msg': 'Domain does not exist.'}
-        headers = {}
-        headers['X-API-Key'] = self.PDNS_API_KEY
+
+        headers = {'X-API-Key': self.PDNS_API_KEY}
 
         if soa_edit_api not in ["DEFAULT", "INCREASE", "EPOCH", "OFF"]:
             soa_edit_api = 'DEFAULT'
@@ -329,13 +324,13 @@ class Domain(db.Model):
         try:
             jdata = utils.fetch_json(urljoin(
                 self.PDNS_STATS_URL, self.API_EXTENDED_URL +
-                '/servers/localhost/zones/{0}'.format(domain.name)),
-                                     headers=headers,
-                                     timeout=int(
-                                         Setting().get('pdns_api_timeout')),
-                                     method='PUT',
-                                     verify=Setting().get('verify_ssl_connections'),
-                                     data=post_data)
+                                     '/servers/localhost/zones/{0}'.format(domain.name)),
+                headers=headers,
+                timeout=int(
+                    Setting().get('pdns_api_timeout')),
+                method='PUT',
+                verify=Setting().get('verify_ssl_connections'),
+                data=post_data)
             if 'error' in jdata.keys():
                 current_app.logger.error(jdata['error'])
                 return {'status': 'error', 'msg': jdata['error']}
@@ -365,21 +360,21 @@ class Domain(db.Model):
         domain = Domain.query.filter(Domain.name == domain_name).first()
         if not domain:
             return {'status': 'error', 'msg': 'Domain does not exist.'}
-        headers = {}
-        headers['X-API-Key'] = self.PDNS_API_KEY
+
+        headers = {'X-API-Key': self.PDNS_API_KEY}
 
         post_data = {"kind": kind, "masters": masters}
 
         try:
             jdata = utils.fetch_json(urljoin(
                 self.PDNS_STATS_URL, self.API_EXTENDED_URL +
-                '/servers/localhost/zones/{0}'.format(domain.name)),
-                                     headers=headers,
-                                     timeout=int(
-                                         Setting().get('pdns_api_timeout')),
-                                     method='PUT',
-                                     verify=Setting().get('verify_ssl_connections'),
-                                     data=post_data)
+                                     '/servers/localhost/zones/{0}'.format(domain.name)),
+                headers=headers,
+                timeout=int(
+                    Setting().get('pdns_api_timeout')),
+                method='PUT',
+                verify=Setting().get('verify_ssl_connections'),
+                data=post_data)
             if 'error' in jdata.keys():
                 current_app.logger.error(jdata['error'])
                 return {'status': 'error', 'msg': jdata['error']}
@@ -410,27 +405,27 @@ class Domain(db.Model):
         domain_obj = Domain.query.filter(Domain.name == domain_name).first()
         domain_auto_ptr = DomainSetting.query.filter(
             DomainSetting.domain == domain_obj).filter(
-                DomainSetting.setting == 'auto_ptr').first()
+            DomainSetting.setting == 'auto_ptr').first()
         domain_auto_ptr = strtobool(
             domain_auto_ptr.value) if domain_auto_ptr else False
         system_auto_ptr = Setting().get('auto_ptr')
         self.name = domain_name
         domain_id = self.get_id_by_name(domain_reverse_name)
-        if None == domain_id and \
-            (
-                system_auto_ptr or
-                domain_auto_ptr
-            ):
-            result = self.add(domain_reverse_name, 'Master', 'DEFAULT', '', '')
+        if domain_id is None and \
+                (
+                        system_auto_ptr or
+                        domain_auto_ptr
+                ):
+            result = self.add(domain_reverse_name, 'Master', 'DEFAULT', [], [])
             self.update()
             if result['status'] == 'ok':
                 history = History(msg='Add reverse lookup domain {0}'.format(
                     domain_reverse_name),
-                                  detail=str({
-                                      'domain_type': 'Master',
-                                      'domain_master_ips': ''
-                                  }),
-                                  created_by='System')
+                    detail=str({
+                        'domain_type': 'Master',
+                        'domain_master_ips': ''
+                    }),
+                    created_by='System')
                 history.add()
             else:
                 return {
@@ -443,9 +438,9 @@ class Domain(db.Model):
                 self.grant_privileges(domain_user_ids)
                 return {
                     'status':
-                    'ok',
+                        'ok',
                     'msg':
-                    'New reverse lookup domain created with granted privileges'
+                        'New reverse lookup domain created with granted privileges'
                 }
             return {
                 'status': 'ok',
@@ -497,16 +492,15 @@ class Domain(db.Model):
         """
         Delete a single domain name from powerdns
         """
-        headers = {}
-        headers['X-API-Key'] = self.PDNS_API_KEY
+        headers = {'X-API-Key': self.PDNS_API_KEY}
 
         utils.fetch_json(urljoin(
             self.PDNS_STATS_URL, self.API_EXTENDED_URL +
-            '/servers/localhost/zones/{0}'.format(domain_name)),
-                         headers=headers,
-                         timeout=int(Setting().get('pdns_api_timeout')),
-                         method='DELETE',
-                         verify=Setting().get('verify_ssl_connections'))
+                                 '/servers/localhost/zones/{0}'.format(domain_name)),
+            headers=headers,
+            timeout=int(Setting().get('pdns_api_timeout')),
+            method='DELETE',
+            verify=Setting().get('verify_ssl_connections'))
         current_app.logger.info(
             'Deleted domain successfully from PowerDNS: {0}'.format(
                 domain_name))
@@ -540,8 +534,8 @@ class Domain(db.Model):
         user_ids = []
         query = db.session.query(
             DomainUser, Domain).filter(User.id == DomainUser.user_id).filter(
-                Domain.id == DomainUser.domain_id).filter(
-                    Domain.name == self.name).all()
+            Domain.id == DomainUser.domain_id).filter(
+            Domain.name == self.name).all()
         for q in query:
             user_ids.append(q[0].user_id)
         return user_ids
@@ -566,7 +560,7 @@ class Domain(db.Model):
             db.session.rollback()
             current_app.logger.error(
                 'Cannot revoke user privileges on domain {0}. DETAIL: {1}'.
-                format(self.name, e))
+                    format(self.name, e))
             current_app.logger.debug(print(traceback.format_exc()))
 
         try:
@@ -578,7 +572,7 @@ class Domain(db.Model):
             db.session.rollback()
             current_app.logger.error(
                 'Cannot grant user privileges to domain {0}. DETAIL: {1}'.
-                format(self.name, e))
+                    format(self.name, e))
             current_app.logger.debug(print(traceback.format_exc()))
 
     def update_from_master(self, domain_name):
@@ -587,27 +581,26 @@ class Domain(db.Model):
         """
         domain = Domain.query.filter(Domain.name == domain_name).first()
         if domain:
-            headers = {}
-            headers['X-API-Key'] = self.PDNS_API_KEY
+            headers = {'X-API-Key': self.PDNS_API_KEY}
             try:
                 r = utils.fetch_json(urljoin(
                     self.PDNS_STATS_URL, self.API_EXTENDED_URL +
-                    '/servers/localhost/zones/{0}/axfr-retrieve'.format(
-                        domain.name)),
-                                     headers=headers,
-                                     timeout=int(
-                                         Setting().get('pdns_api_timeout')),
-                                     method='PUT',
-                                     verify=Setting().get('verify_ssl_connections'))
+                                         '/servers/localhost/zones/{0}/axfr-retrieve'.format(
+                                             domain.name)),
+                    headers=headers,
+                    timeout=int(
+                        Setting().get('pdns_api_timeout')),
+                    method='PUT',
+                    verify=Setting().get('verify_ssl_connections'))
                 return {'status': 'ok', 'msg': r.get('result')}
             except Exception as e:
                 current_app.logger.error(
                     'Cannot update from master. DETAIL: {0}'.format(e))
                 return {
                     'status':
-                    'error',
+                        'error',
                     'msg':
-                    'There was something wrong, please contact administrator'
+                        'There was something wrong, please contact administrator'
                 }
         else:
             return {'status': 'error', 'msg': 'This domain does not exist'}
@@ -618,14 +611,13 @@ class Domain(db.Model):
         """
         domain = Domain.query.filter(Domain.name == domain_name).first()
         if domain:
-            headers = {}
-            headers['X-API-Key'] = self.PDNS_API_KEY
+            headers = {'X-API-Key': self.PDNS_API_KEY}
             try:
                 jdata = utils.fetch_json(
                     urljoin(
                         self.PDNS_STATS_URL, self.API_EXTENDED_URL +
-                        '/servers/localhost/zones/{0}/cryptokeys'.format(
-                            domain.name)),
+                                             '/servers/localhost/zones/{0}/cryptokeys'.format(
+                                                 domain.name)),
                     headers=headers,
                     timeout=int(Setting().get('pdns_api_timeout')),
                     method='GET',
@@ -642,9 +634,9 @@ class Domain(db.Model):
                     'Cannot get domain dnssec. DETAIL: {0}'.format(e))
                 return {
                     'status':
-                    'error',
+                        'error',
                     'msg':
-                    'There was something wrong, please contact administrator'
+                        'There was something wrong, please contact administrator'
                 }
         else:
             return {'status': 'error', 'msg': 'This domain does not exist'}
@@ -655,15 +647,14 @@ class Domain(db.Model):
         """
         domain = Domain.query.filter(Domain.name == domain_name).first()
         if domain:
-            headers = {}
-            headers['X-API-Key'] = self.PDNS_API_KEY
+            headers = {'X-API-Key': self.PDNS_API_KEY}
             try:
                 # Enable API-RECTIFY for domain, BEFORE activating DNSSEC
                 post_data = {"api_rectify": True}
                 jdata = utils.fetch_json(
                     urljoin(
                         self.PDNS_STATS_URL, self.API_EXTENDED_URL +
-                        '/servers/localhost/zones/{0}'.format(domain.name)),
+                                             '/servers/localhost/zones/{0}'.format(domain.name)),
                     headers=headers,
                     timeout=int(Setting().get('pdns_api_timeout')),
                     method='PUT',
@@ -673,7 +664,7 @@ class Domain(db.Model):
                     return {
                         'status': 'error',
                         'msg':
-                        'API-RECTIFY could not be enabled for this domain',
+                            'API-RECTIFY could not be enabled for this domain',
                         'jdata': jdata
                     }
 
@@ -682,8 +673,8 @@ class Domain(db.Model):
                 jdata = utils.fetch_json(
                     urljoin(
                         self.PDNS_STATS_URL, self.API_EXTENDED_URL +
-                        '/servers/localhost/zones/{0}/cryptokeys'.format(
-                            domain.name)),
+                                             '/servers/localhost/zones/{0}/cryptokeys'.format(
+                                                 domain.name)),
                     headers=headers,
                     timeout=int(Setting().get('pdns_api_timeout')),
                     method='POST',
@@ -692,12 +683,12 @@ class Domain(db.Model):
                 if 'error' in jdata:
                     return {
                         'status':
-                        'error',
+                            'error',
                         'msg':
-                        'Cannot enable DNSSEC for this domain. Error: {0}'.
-                        format(jdata['error']),
+                            'Cannot enable DNSSEC for this domain. Error: {0}'.
+                                format(jdata['error']),
                         'jdata':
-                        jdata
+                            jdata
                     }
 
                 return {'status': 'ok'}
@@ -708,9 +699,9 @@ class Domain(db.Model):
                 current_app.logger.debug(traceback.format_exc())
                 return {
                     'status':
-                    'error',
+                        'error',
                     'msg':
-                    'There was something wrong, please contact administrator'
+                        'There was something wrong, please contact administrator'
                 }
 
         else:
@@ -722,15 +713,14 @@ class Domain(db.Model):
         """
         domain = Domain.query.filter(Domain.name == domain_name).first()
         if domain:
-            headers = {}
-            headers['X-API-Key'] = self.PDNS_API_KEY
+            headers = {'X-API-Key': self.PDNS_API_KEY}
             try:
                 # Deactivate DNSSEC
                 jdata = utils.fetch_json(
                     urljoin(
                         self.PDNS_STATS_URL, self.API_EXTENDED_URL +
-                        '/servers/localhost/zones/{0}/cryptokeys/{1}'.format(
-                            domain.name, key_id)),
+                                             '/servers/localhost/zones/{0}/cryptokeys/{1}'.format(
+                                                 domain.name, key_id)),
                     headers=headers,
                     timeout=int(Setting().get('pdns_api_timeout')),
                     method='DELETE',
@@ -738,12 +728,12 @@ class Domain(db.Model):
                 if jdata != True:
                     return {
                         'status':
-                        'error',
+                            'error',
                         'msg':
-                        'Cannot disable DNSSEC for this domain. Error: {0}'.
-                        format(jdata['error']),
+                            'Cannot disable DNSSEC for this domain. Error: {0}'.
+                                format(jdata['error']),
                         'jdata':
-                        jdata
+                            jdata
                     }
 
                 # Disable API-RECTIFY for domain, AFTER deactivating DNSSEC
@@ -751,7 +741,7 @@ class Domain(db.Model):
                 jdata = utils.fetch_json(
                     urljoin(
                         self.PDNS_STATS_URL, self.API_EXTENDED_URL +
-                        '/servers/localhost/zones/{0}'.format(domain.name)),
+                                             '/servers/localhost/zones/{0}'.format(domain.name)),
                     headers=headers,
                     timeout=int(Setting().get('pdns_api_timeout')),
                     method='PUT',
@@ -761,7 +751,7 @@ class Domain(db.Model):
                     return {
                         'status': 'error',
                         'msg':
-                        'API-RECTIFY could not be disabled for this domain',
+                            'API-RECTIFY could not be disabled for this domain',
                         'jdata': jdata
                     }
 
@@ -774,7 +764,7 @@ class Domain(db.Model):
                 return {
                     'status': 'error',
                     'msg':
-                    'There was something wrong, please contact administrator',
+                        'There was something wrong, please contact administrator',
                     'domain': domain.name,
                     'id': key_id
                 }
@@ -797,8 +787,7 @@ class Domain(db.Model):
         if not domain:
             return {'status': False, 'msg': 'Domain does not exist'}
 
-        headers = {}
-        headers['X-API-Key'] = self.PDNS_API_KEY
+        headers = {'X-API-Key': self.PDNS_API_KEY}
 
         account_name = Account().get_name_by_id(account_id)
 
@@ -807,13 +796,13 @@ class Domain(db.Model):
         try:
             jdata = utils.fetch_json(urljoin(
                 self.PDNS_STATS_URL, self.API_EXTENDED_URL +
-                '/servers/localhost/zones/{0}'.format(domain_name)),
-                                     headers=headers,
-                                     timeout=int(
-                                         Setting().get('pdns_api_timeout')),
-                                     method='PUT',
-                                     verify=Setting().get('verify_ssl_connections'),
-                                     data=post_data)
+                                     '/servers/localhost/zones/{0}'.format(domain_name)),
+                headers=headers,
+                timeout=int(
+                    Setting().get('pdns_api_timeout')),
+                method='PUT',
+                verify=Setting().get('verify_ssl_connections'),
+                data=post_data)
 
             if 'error' in jdata.keys():
                 current_app.logger.error(jdata['error'])
@@ -852,7 +841,7 @@ class Domain(db.Model):
             .outerjoin(Account, Domain.account_id == Account.id) \
             .outerjoin(AccountUser, Account.id == AccountUser.account_id) \
             .filter(
-                db.or_(
-                    DomainUser.user_id == user_id,
-                    AccountUser.user_id == user_id
-                )).filter(Domain.id == self.id).first()
+            db.or_(
+                DomainUser.user_id == user_id,
+                AccountUser.user_id == user_id
+            )).filter(Domain.id == self.id).first()
diff --git a/powerdnsadmin/models/domain_setting.py b/powerdnsadmin/models/domain_setting.py
index 849239c..91dcb2e 100644
--- a/powerdnsadmin/models/domain_setting.py
+++ b/powerdnsadmin/models/domain_setting.py
@@ -1,3 +1,5 @@
+import traceback
+
 from flask import current_app
 
 from .base import db
@@ -32,4 +34,4 @@ class DomainSetting(db.Model):
                 'Unable to set DomainSetting value. DETAIL: {0}'.format(e))
             current_app.logger.debug(traceback.format_exc())
             db.session.rollback()
-            return False
\ No newline at end of file
+            return False
diff --git a/powerdnsadmin/models/domain_user.py b/powerdnsadmin/models/domain_user.py
index e556339..7b24a53 100644
--- a/powerdnsadmin/models/domain_user.py
+++ b/powerdnsadmin/models/domain_user.py
@@ -14,4 +14,4 @@ class DomainUser(db.Model):
         self.user_id = user_id
 
     def __repr__(self):
-        return '<Domain_User {0} {1}>'.format(self.domain_id, self.user_id)
\ No newline at end of file
+        return '<Domain_User {0} {1}>'.format(self.domain_id, self.user_id)
diff --git a/powerdnsadmin/models/history.py b/powerdnsadmin/models/history.py
index 70ef43a..709a911 100644
--- a/powerdnsadmin/models/history.py
+++ b/powerdnsadmin/models/history.py
@@ -1,3 +1,5 @@
+import traceback
+
 from flask import current_app
 from datetime import datetime
 
diff --git a/powerdnsadmin/models/record.py b/powerdnsadmin/models/record.py
index 2a9ff71..201ad82 100644
--- a/powerdnsadmin/models/record.py
+++ b/powerdnsadmin/models/record.py
@@ -14,12 +14,11 @@ from .setting import Setting
 from .domain import Domain
 from .domain_setting import DomainSetting
 
-def byRecordContent(e):
-    return e['content']
 
-def byRecordContentPair(e):
+def by_record_content_pair(e):
     return e[0]['content']
 
+
 class Record(object):
     """
     This is not a model, it's just an object
@@ -49,8 +48,7 @@ class Record(object):
         """
         Query domain's rrsets via PDNS API
         """
-        headers = {}
-        headers['X-API-Key'] = self.PDNS_API_KEY
+        headers = {'X-API-Key': self.PDNS_API_KEY}
         try:
             jdata = utils.fetch_json(urljoin(
                 self.PDNS_STATS_URL, self.API_EXTENDED_URL +
@@ -68,8 +66,8 @@ class Record(object):
         rrsets=[]
         for r in jdata['rrsets']:
             while len(r['comments'])<len(r['records']):
-                r['comments'].append({"content":"", "account":""})
-            r['records'], r['comments'] = (list(t) for t in zip(*sorted(zip(r['records'],r['comments']),key=byRecordContentPair)))
+                r['comments'].append({"content": "", "account": ""})
+            r['records'], r['comments'] = (list(t) for t in zip(*sorted(zip(r['records'], r['comments']), key=by_record_content_pair)))
             rrsets.append(r)
 
         return rrsets
@@ -98,8 +96,7 @@ class Record(object):
                 }
 
         # Continue if the record is ready to be added
-        headers = {}
-        headers['X-API-Key'] = self.PDNS_API_KEY
+        headers = {'X-API-Key': self.PDNS_API_KEY}
 
         try:
             jdata = utils.fetch_json(urljoin(
@@ -129,26 +126,26 @@ class Record(object):
         """
         Merge the rrsets that has same "name" and
         "type".
-        Return: a new rrest which has multiple "records"
+        Return: a new rrset which has multiple "records"
         and "comments"
         """
         if not rrsets:
             raise Exception("Empty rrsets to merge")
         elif len(rrsets) == 1:
-            # It is unique rrest already
+            # It is unique rrset already
             return rrsets[0]
         else:
             # Merge rrsets into one
-            rrest = rrsets[0]
+            rrset = rrsets[0]
             for r in rrsets[1:]:
-                rrest['records'] = rrest['records'] + r['records']
-                rrest['comments'] = rrest['comments'] + r['comments']
-            while len(rrest['comments'])<len(rrest['records']):
-                rrest['comments'].append({"content":"", "account":""})
-            zipped_list = zip(rrest['records'],rrest['comments'])
-            tuples = zip(*sorted(zipped_list,key=byRecordContentPair))
-            rrest['records'], rrest['comments'] = [list(t) for t in tuples]
-            return rrest
+                rrset['records'] = rrset['records'] + r['records']
+                rrset['comments'] = rrset['comments'] + r['comments']
+            while len(rrset['comments']) < len(rrset['records']):
+                rrset['comments'].append({"content": "", "account": ""})
+            zipped_list = zip(rrset['records'], rrset['comments'])
+            tuples = zip(*sorted(zipped_list, key=by_record_content_pair))
+            rrset['records'], rrset['comments'] = [list(t) for t in tuples]
+            return rrset
 
     def build_rrsets(self, domain_name, submitted_records):
         """
@@ -159,7 +156,7 @@ class Record(object):
             submitted_records(list): List of records submitted from PDA datatable
 
         Returns:
-            transformed_rrsets(list): List of rrests converted from PDA datatable
+            transformed_rrsets(list): List of rrsets converted from PDA datatable
         """
         rrsets = []
         for record in submitted_records:
@@ -192,7 +189,7 @@ class Record(object):
             ] and record["record_data"].strip()[-1:] != '.':
                 record["record_data"] += '.'
 
-            record_conntent = {
+            record_content = {
                 "content": record["record_data"],
                 "disabled":
                 False if record['record_status'] == 'Active' else True
@@ -212,12 +209,12 @@ class Record(object):
                 "name": record_name,
                 "type": record["record_type"],
                 "ttl": int(record["record_ttl"]),
-                "records": [record_conntent],
+                "records": [record_content],
                 "comments": record_comments
             })
 
         # Group the records which has the same name and type.
-        # The rrest then has multiple records inside.
+        # The rrset then has multiple records inside.
         transformed_rrsets = []
 
         # Sort the list before using groupby
@@ -238,8 +235,8 @@ class Record(object):
             submitted_records(list): List of records submitted from PDA datatable
 
         Returns:
-            new_rrsets(list): List of rrests to be added
-            del_rrsets(list): List of rrests to be deleted
+            new_rrsets(list): List of rrsets to be added
+            del_rrsets(list): List of rrsets to be deleted
         """
         # Create submitted rrsets from submitted records
         submitted_rrsets = self.build_rrsets(domain_name, submitted_records)
@@ -285,7 +282,7 @@ class Record(object):
         """
         Apply record changes to a domain. This function
         will make 2 calls to the PDNS API to DELETE and
-        REPLACE records (rrests)
+        REPLACE records (rrsets)
         """
         current_app.logger.debug(
             "submitted_records: {}".format(submitted_records))
@@ -293,7 +290,7 @@ class Record(object):
         # Get the list of rrsets to be added and deleted
         new_rrsets, del_rrsets = self.compare(domain_name, submitted_records)
 
-        # Remove blank comments from rrsets for compatability with some backends
+        # Remove blank comments from rrsets for compatibility with some backends
         for r in new_rrsets['rrsets']:
             if not r['comments']:
                 del r['comments']
@@ -304,8 +301,7 @@ class Record(object):
 
         # Submit the changes to PDNS API
         try:
-            headers = {}
-            headers['X-API-Key'] = self.PDNS_API_KEY
+            headers = {'X-API-Key': self.PDNS_API_KEY}
 
             if del_rrsets["rrsets"]:
                 jdata1 = utils.fetch_json(urljoin(
@@ -467,8 +463,7 @@ class Record(object):
         """
         Delete a record from domain
         """
-        headers = {}
-        headers['X-API-Key'] = self.PDNS_API_KEY
+        headers = {'X-API-Key': self.PDNS_API_KEY}
         data = {
             "rrsets": [{
                 "name": self.name.rstrip('.') + '.',
@@ -530,8 +525,7 @@ class Record(object):
         """
         Update single record
         """
-        headers = {}
-        headers['X-API-Key'] = self.PDNS_API_KEY
+        headers = {'X-API-Key': self.PDNS_API_KEY}
 
         data = {
             "rrsets": [{
@@ -572,8 +566,7 @@ class Record(object):
             }
 
     def update_db_serial(self, domain):
-        headers = {}
-        headers['X-API-Key'] = self.PDNS_API_KEY
+        headers = {'X-API-Key': self.PDNS_API_KEY}
         jdata = utils.fetch_json(urljoin(
             self.PDNS_STATS_URL, self.API_EXTENDED_URL +
             '/servers/localhost/zones/{0}'.format(domain)),
diff --git a/powerdnsadmin/models/record_entry.py b/powerdnsadmin/models/record_entry.py
index 5b8584b..468f6ef 100644
--- a/powerdnsadmin/models/record_entry.py
+++ b/powerdnsadmin/models/record_entry.py
@@ -24,4 +24,4 @@ class RecordEntry(object):
         return self._is_allowed_edit
 
     def is_allowed_delete(self):
-        return self._is_allowed_delete
\ No newline at end of file
+        return self._is_allowed_delete
diff --git a/powerdnsadmin/models/role.py b/powerdnsadmin/models/role.py
index 8833cbd..a5cf530 100644
--- a/powerdnsadmin/models/role.py
+++ b/powerdnsadmin/models/role.py
@@ -20,4 +20,4 @@ class Role(db.Model):
         self.description = description
 
     def __repr__(self):
-        return '<Role {0}r>'.format(self.name)
\ No newline at end of file
+        return '<Role {0}r>'.format(self.name)
diff --git a/powerdnsadmin/models/server.py b/powerdnsadmin/models/server.py
index cdcd6f0..ce5b27f 100644
--- a/powerdnsadmin/models/server.py
+++ b/powerdnsadmin/models/server.py
@@ -24,8 +24,7 @@ class Server(object):
         """
         Get server config
         """
-        headers = {}
-        headers['X-API-Key'] = self.PDNS_API_KEY
+        headers = {'X-API-Key': self.PDNS_API_KEY}
 
         try:
             jdata = utils.fetch_json(urljoin(
@@ -46,8 +45,7 @@ class Server(object):
         """
         Get server statistics
         """
-        headers = {}
-        headers['X-API-Key'] = self.PDNS_API_KEY
+        headers = {'X-API-Key': self.PDNS_API_KEY}
 
         try:
             jdata = utils.fetch_json(urljoin(
@@ -68,8 +66,7 @@ class Server(object):
         """
         Search zone/record/comment directly from PDNS API
         """
-        headers = {}
-        headers['X-API-Key'] = self.PDNS_API_KEY
+        headers = {'X-API-Key': self.PDNS_API_KEY}
 
         try:
             jdata = utils.fetch_json(urljoin(
diff --git a/powerdnsadmin/models/setting.py b/powerdnsadmin/models/setting.py
index 0f6f35d..9e5aba3 100644
--- a/powerdnsadmin/models/setting.py
+++ b/powerdnsadmin/models/setting.py
@@ -1,4 +1,6 @@
 import sys
+import traceback
+
 import pytimeparse
 from ast import literal_eval
 from distutils.util import strtobool
diff --git a/powerdnsadmin/routes/user.py b/powerdnsadmin/routes/user.py
index b623736..a6abce3 100644
--- a/powerdnsadmin/routes/user.py
+++ b/powerdnsadmin/routes/user.py
@@ -50,7 +50,7 @@ def profile():
                 'password'] if 'password' in request.form else ''
         else:
             firstname = lastname = email = new_password = ''
-            logging.warning(
+            current_app.logger.warning(
                 'Authenticated externally. User {0} information will not allowed to update the profile'
                 .format(current_user.username))