diff --git a/PyLoT.py b/PyLoT.py
index 8ba8d7a6..deee5399 100755
--- a/PyLoT.py
+++ b/PyLoT.py
@@ -1492,7 +1492,7 @@ class MainWindow(QMainWindow):
         wf_dir = wf_stat[self.data.processed]
         if wf_dir is not None:
             wf_path = os.path.join(event_path, wf_dir)
-            if wf_dir is 'processed' and not os.path.exists(wf_path):
+            if wf_dir == 'processed' and not os.path.exists(wf_path):
                 wf_path = os.path.join(event_path, 'raw')
         else:
             wf_path = event_path
diff --git a/autoPyLoT.py b/autoPyLoT.py
index 703f068d..3441ecc1 100755
--- a/autoPyLoT.py
+++ b/autoPyLoT.py
@@ -145,7 +145,7 @@ def autoPyLoT(input_dict=None, parameter=None, inputfile=None, fnames=None, even
 
         exf = ['root', 'dpath', 'dbase']
 
-        if parameter['eventID'] is not '*' and fnames == 'None':
+        if parameter['eventID'] != '*' and fnames == 'None':
             dsfields['eventID'] = parameter['eventID']
             exf.append('eventID')
 
@@ -189,12 +189,12 @@ def autoPyLoT(input_dict=None, parameter=None, inputfile=None, fnames=None, even
         if not input_dict:
             # started in production mode
             datapath = datastructure.expandDataPath()
-            if fnames == 'None' and parameter['eventID'] is '*':
+            if fnames == 'None' and parameter['eventID'] != '*':
                 # multiple event processing
                 # read each event in database
                 events = [event for event in glob.glob(os.path.join(datapath, '*')) if
                           (os.path.isdir(event) and not event.endswith('EVENTS-INFO'))]
-            elif fnames == 'None' and parameter['eventID'] is not '*' and not type(parameter['eventID']) == list:
+            elif fnames == 'None' and parameter['eventID'] != '*' and not type(parameter['eventID']) == list:
                 # single event processing
                 events = glob.glob(os.path.join(datapath, parameter['eventID']))
             elif fnames == 'None' and type(parameter['eventID']) == list:
diff --git a/pylot/core/io/data.py b/pylot/core/io/data.py
index 11a627aa..746df729 100644
--- a/pylot/core/io/data.py
+++ b/pylot/core/io/data.py
@@ -55,7 +55,7 @@ class Data(object):
         elif type(evtdata) in str_TypeLst:
             try:
                 cat = read_events(evtdata)
-                if len(cat) is not 1:
+                if len(cat) != 1:
                     raise ValueError('ambiguous event information for file: '
                                      '{file}'.format(file=evtdata))
                 evtdata = cat[0]
@@ -322,7 +322,7 @@ class Data(object):
                             del picks_copy[k]
                             break
             lendiff = len(picks) - len(picks_copy)
-            if lendiff is not 0:
+            if lendiff != 0:
                 print("Manual as well as automatic picks available. Prefered the {} manual ones!".format(lendiff))
 
             if upperErrors:
diff --git a/pylot/core/io/phases.py b/pylot/core/io/phases.py
index fb974770..3be89582 100644
--- a/pylot/core/io/phases.py
+++ b/pylot/core/io/phases.py
@@ -232,7 +232,7 @@ def picksdict_from_picks(evt):
     for pick in evt.picks:
         phase = {}
         station = pick.waveform_id.station_code
-        if pick.waveform_id.channel_code == None:
+        if pick.waveform_id.channel_code is None:
             channel = ''
         else:
             channel = pick.waveform_id.channel_code
@@ -774,7 +774,7 @@ def writephases(arrivals, fformat, filename, parameter=None, eventinfo=None):
                     Ponset = arrivals[key]['P']['mpp']
                     Pweight = arrivals[key]['P']['weight']
                     Prt = Ponset - stime  # onset time relative to source time
-                    if n % 6 is not 0:
+                    if n % 6 != 0:
                         fid.write('%-4sP%d%6.2f' % (stat, Pweight, Prt))
                     else:
                         fid.write('%-4sP%d%6.2f\n' % (stat, Pweight, Prt))
@@ -788,7 +788,7 @@ def writephases(arrivals, fformat, filename, parameter=None, eventinfo=None):
                     Sonset = arrivals[key]['S']['mpp']
                     Sweight = arrivals[key]['S']['weight']
                     Srt = Ponset - stime  # onset time relative to source time
-                    if n % 6 is not 0:
+                    if n % 6 != 0:
                         fid.write('%-4sS%d%6.2f' % (stat, Sweight, Srt))
                     else:
                         fid.write('%-4sS%d%6.2f\n' % (stat, Sweight, Srt))
@@ -1080,7 +1080,7 @@ def getQualitiesfromxml(xmlnames, ErrorsP, ErrorsS, plotflag=1):
                             del mpick
                             break
         lendiff = len(arrivals) - len(arrivals_copy)
-        if lendiff is not 0:
+        if lendiff != 0:
             print("Found manual as well as automatic picks, prefered the {} manual ones!".format(lendiff))
 
         for Pick in arrivals_copy:
diff --git a/pylot/core/pick/charfuns.py b/pylot/core/pick/charfuns.py
index c589bdea..45892fd4 100644
--- a/pylot/core/pick/charfuns.py
+++ b/pylot/core/pick/charfuns.py
@@ -150,7 +150,7 @@ class CharacteristicFunction(object):
                 if self.cut[0] == 0 and self.cut[1] == 0:
                     start = 0
                     stop = len(self.orig_data[0])
-                elif self.cut[0] == 0 and self.cut[1] is not 0:
+                elif self.cut[0] == 0 and self.cut[1] != 0:
                     start = 0
                     stop = self.cut[1] / self.dt
                 else:
@@ -167,7 +167,7 @@ class CharacteristicFunction(object):
                 if self.cut[0] == 0 and self.cut[1] == 0:
                     start = 0
                     stop = min([len(self.orig_data[0]), len(self.orig_data[1])])
-                elif self.cut[0] == 0 and self.cut[1] is not 0:
+                elif self.cut[0] == 0 and self.cut[1] != 0:
                     start = 0
                     stop = min([self.cut[1] / self.dt, len(self.orig_data[0]),
                                 len(self.orig_data[1])])
@@ -187,7 +187,7 @@ class CharacteristicFunction(object):
                     start = 0
                     stop = min([self.cut[1] / self.dt, len(self.orig_data[0]),
                                 len(self.orig_data[1]), len(self.orig_data[2])])
-                elif self.cut[0] == 0 and self.cut[1] is not 0:
+                elif self.cut[0] == 0 and self.cut[1] != 0:
                     start = 0
                     stop = self.cut[1] / self.dt
                 else:
diff --git a/pylot/core/util/array_map.py b/pylot/core/util/array_map.py
index fe48a0de..504bdc4d 100644
--- a/pylot/core/util/array_map.py
+++ b/pylot/core/util/array_map.py
@@ -5,8 +5,6 @@ import sys
 import os
 import matplotlib
 
-matplotlib.use('Qt5Agg')
-
 from PySide2 import QtCore, QtGui, QtWidgets
 from PySide2.QtCore import Qt
 from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
@@ -29,6 +27,9 @@ from scipy.interpolate import griddata
 from pylot.core.util.widgets import PickDlg
 from pylot.core.pick.utils import get_quality_class
 
+matplotlib.use('Qt5Agg')
+
+
 
 class MplCanvas(FigureCanvas):
 
@@ -49,7 +50,7 @@ class Array_map(QtWidgets.QWidget):
         # super(Array_map, self).__init__(parent)
         QtWidgets.QWidget.__init__(self)
 
-        assert (parameter != None or parent != None), 'either parent or parameter has to be set'
+        assert (parameter is not None or parent is not None), 'either parent or parameter has to be set'
         # set properties
         self._parent = parent
         self.metadata = metadata
diff --git a/pylot/core/util/utils.py b/pylot/core/util/utils.py
index d44f639c..fa53165c 100644
--- a/pylot/core/util/utils.py
+++ b/pylot/core/util/utils.py
@@ -227,7 +227,7 @@ def findComboBoxIndex(combo_box, val):
     :type val: basestring
     :return: index value of item with name val or 0
     """
-    return combo_box.findText(val) if combo_box.findText(val) is not -1 else 0
+    return combo_box.findText(val) if combo_box.findText(val) != -1 else 0
 
 
 def find_in_list(list, str):
@@ -1016,7 +1016,7 @@ def scaleWFData(data, factor=None, components='all'):
     :return:  scaled waveform data
     :rtype: `~obspy.core.stream.Stream` object
     """
-    if components is not 'all':
+    if components != 'all':
         for comp in components:
             if factor is None:
                 max_val = np.max(np.abs(data.select(component=comp)[0].data))
diff --git a/setup.py b/setup.py
index 09f8e357..25e80a90 100644
--- a/setup.py
+++ b/setup.py
@@ -8,7 +8,7 @@ setup(
     packages=['pylot', 'pylot.core', 'pylot.core.loc', 'pylot.core.pick',
               'pylot.core.io', 'pylot.core.util', 'pylot.core.active',
               'pylot.core.analysis', 'pylot.testing'],
-    requires=['obspy', 'PySide', 'matplotlib', 'numpy', 'scipy', 'pyqtgraph'],
+    requires=['obspy', 'PySide2', 'matplotlib', 'numpy', 'scipy', 'pyqtgraph', 'cartopy'],
     url='dummy',
     license='LGPLv3',
     author='Sebastian Wehling-Benatelli',