diff --git a/.gitignore b/.gitignore
index 721c2b8..d2caed8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -12,3 +12,5 @@ distances-aligned.csv
 i18n/*.qm
 DistanceMatrixToCoords.zip
 i18n/latest_run
+
+.coverage
\ No newline at end of file
diff --git a/ghini_tree_position.py b/ghini_tree_position.py
index 3d8c157..129941c 100644
--- a/ghini_tree_position.py
+++ b/ghini_tree_position.py
@@ -394,10 +394,10 @@ def _sink(self, index):
 
         """
         while True:
-            maxleafindex = (index+1)*2-1
+            maxleafindex = (index + 1) * 2 - 1
             try:
                 if self.heap[maxleafindex]['prio'] < self.heap[
-                        maxleafindex+1]['prio']:
+                        maxleafindex + 1]['prio']:
                     maxleafindex += 1
             except IndexError:
                 pass
diff --git a/test/__init__.py b/test/__init__.py
index 8feeb0b..4b0c092 100644
--- a/test/__init__.py
+++ b/test/__init__.py
@@ -1,2 +1,2 @@
 # import qgis libs so that ve set the correct sip api version
-import qgis   # pylint: disable=W0611  # NOQA
\ No newline at end of file
+import qgis   # pylint: disable=W0611  # NOQA
diff --git a/test/qgis_interface.py b/test/qgis_interface.py
index 607c100..1cdfa1d 100644
--- a/test/qgis_interface.py
+++ b/test/qgis_interface.py
@@ -13,6 +13,10 @@
      Copyright (c) 2014 Tim Sutton, tim@linfiniti.com
 
 """
+import logging
+from PyQt4.QtCore import QObject, pyqtSlot, pyqtSignal
+from qgis.core import QgsMapLayerRegistry
+from qgis.gui import QgsMapCanvasLayer
 
 __author__ = 'tim@linfiniti.com'
 __revision__ = '$Format:%H$'
@@ -23,14 +27,10 @@
     'Copyright (c) 2014 Tim Sutton, tim@linfiniti.com'
 )
 
-import logging
-from PyQt4.QtCore import QObject, pyqtSlot, pyqtSignal
-from qgis.core import QgsMapLayerRegistry
-from qgis.gui import QgsMapCanvasLayer
 LOGGER = logging.getLogger('QGIS')
 
 
-#noinspection PyMethodMayBeStatic,PyPep8Naming
+# noinspection PyMethodMayBeStatic,PyPep8Naming
 class QgisInterface(QObject):
     """Class to expose QGIS objects and functions to plugins.
 
@@ -67,9 +67,9 @@ def addLayers(self, layers):
         .. note:: The QgsInterface api does not include this method,
             it is added here as a helper to facilitate testing.
         """
-        #LOGGER.debug('addLayers called on qgis_interface')
-        #LOGGER.debug('Number of layers being added: %s' % len(layers))
-        #LOGGER.debug('Layer Count Before: %s' % len(self.canvas.layers()))
+        # LOGGER.debug('addLayers called on qgis_interface')
+        # LOGGER.debug('Number of layers being added: %s' % len(layers))
+        # LOGGER.debug('Layer Count Before: %s' % len(self.canvas.layers()))
         current_layers = self.canvas.layers()
         final_layers = []
         for layer in current_layers:
@@ -78,7 +78,7 @@ def addLayers(self, layers):
             final_layers.append(QgsMapCanvasLayer(layer))
 
         self.canvas.setLayerSet(final_layers)
-        #LOGGER.debug('Layer Count After: %s' % len(self.canvas.layers()))
+        # LOGGER.debug('Layer Count After: %s' % len(self.canvas.layers()))
 
     @pyqtSlot('QgsMapLayer')
     def addLayer(self, layer):
diff --git a/test/test_ghini_tree_position_dialog.py b/test/test_ghini_tree_position_dialog.py
index d10d175..6b198c7 100644
--- a/test/test_ghini_tree_position_dialog.py
+++ b/test/test_ghini_tree_position_dialog.py
@@ -8,17 +8,15 @@
 
 """
 
-__author__ = 'mario@anche.no'
-__date__ = '2017-01-04'
-__copyright__ = 'Copyright 2017, Mario Frasca'
-
 import unittest
-
 from PyQt4.QtGui import QDialogButtonBox, QDialog
-
 from ghini_tree_position_dialog import DistanceMatrixToCoordsDialog
-
 from utilities import get_qgis_app
+
+__author__ = 'mario@anche.no'
+__date__ = '2017-01-04'
+__copyright__ = 'Copyright 2017, Mario Frasca'
+
 QGIS_APP = get_qgis_app()
 
 
@@ -52,4 +50,3 @@ def test_dialog_cancel(self):
     suite = unittest.makeSuite(DistanceMatrixToCoordsDialogTest)
     runner = unittest.TextTestRunner(verbosity=2)
     runner.run(suite)
-
diff --git a/test/test_heap.py b/test/test_heap.py
index 79abab1..73b0c20 100644
--- a/test/test_heap.py
+++ b/test/test_heap.py
@@ -2,21 +2,26 @@
 
 from ghini_tree_position import Heap
 
+
 class HeapTest(unittest.TestCase):
     def test_init(self):
-        i = Heap([{'prio':1},{'prio':2},{'prio':3}])
+        i = Heap([{'prio': 1}, {'prio': 2}, {'prio': 3}])
         print(dir(self))
         self.assertEquals(i.priorities(), [3, 1, 2])
-        i = Heap([{'prio':1},{'prio':2},{'prio':3},{'prio':4},{'prio':5}])
+        i = Heap([{'prio': 1}, {'prio': 2}, {'prio': 3}, {'prio': 4},
+                  {'prio': 5}])
         self.assertEquals(i.priorities(), [5, 4, 2, 1, 3])
-        i = Heap([{'prio':1},{'prio':3},{'prio':2},{'prio':4},{'prio':5}])
+        i = Heap([{'prio': 1}, {'prio': 3}, {'prio': 2}, {'prio': 4},
+                  {'prio': 5}])
         self.assertEquals(i.priorities(), [5, 4, 2, 1, 3])
-        i = Heap([{'prio':1},{'prio':2},{'prio':3},{'prio':4},{'prio':5},{'prio':7}])
+        i = Heap([{'prio': 1}, {'prio': 2}, {'prio': 3}, {'prio': 4},
+                  {'prio': 5}, {'prio': 7}])
         self.assertEquals(i.priorities(), [7, 4, 5, 1, 3, 2])
 
     def test_push(self):
 
-        i = Heap([{'prio':1},{'prio':2},{'prio':3},{'prio':4},{'prio':5},{'prio':7}])
+        i = Heap([{'prio': 1}, {'prio': 2}, {'prio': 3}, {'prio': 4},
+                  {'prio': 5}, {'prio': 7}])
         i.push({'prio': 8})
         self.assertEquals(i.pop(), {'prio': 8})
         i.push({'prio': 6})
@@ -25,7 +30,8 @@ def test_push(self):
 
     def test_pop(self):
 
-        i = Heap([{'prio':1},{'prio':2},{'prio':3},{'prio':4},{'prio':5},{'prio':7}])
+        i = Heap([{'prio': 1}, {'prio': 2}, {'prio': 3}, {'prio': 4},
+                  {'prio': 5}, {'prio': 7}])
         self.assertEquals(i.pop(), {'prio': 7})
         self.assertEquals(i.pop(), {'prio': 5})
         self.assertEquals(i.pop(), {'prio': 4})
@@ -34,7 +40,8 @@ def test_pop(self):
         self.assertEquals(i.pop(), {'prio': 1})
         self.assertEquals(len(i.priorities()), 0)
 
-        a, b, c, d, e, f = ({'prio':1},{'prio':2},{'prio':3},{'prio':4},{'prio':5},{'prio':7})
+        a, b, c, d, e, f = ({'prio': 1}, {'prio': 2}, {'prio': 3}, {'prio': 4},
+                            {'prio': 5}, {'prio': 7})
         i = Heap([f, e, b, c, d, a])
         self.assertEquals(i.priorities(), [7, 5, 2, 3, 4, 1])
         self.assertEquals(i.pop(), {'prio': 7})
@@ -44,17 +51,19 @@ def test_pop(self):
 
     def test_reprioritize(self):
 
-        a, b, c, d, e, f = ({'prio':1},{'prio':2},{'prio':3},{'prio':4},{'prio':5},{'prio':7})
+        a, b, c, d, e, f = ({'prio': 1}, {'prio': 2}, {'prio': 3}, {'prio': 4},
+                            {'prio': 5}, {'prio': 7})
         i = Heap([a, b, c, d, e, f])
 
-        ## nothing happens if the priority change is zero
+        # nothing happens if the priority change is zero
         self.assertEquals(i.priorities(), [7, 4, 5, 1, 3, 2])
         i.reprioritize(a, 0)
         self.assertEquals(i.priorities(), [7, 4, 5, 1, 3, 2])
 
-        ## the priority change default value is the positive unit. you specify
-        ## the object of which the priority has to be altered.
-        a, b, c, d, e, f = ({'prio':1},{'prio':2},{'prio':3},{'prio':4},{'prio':5},{'prio':7})
+        # the priority change default value is the positive unit. you specify
+        # the object of which the priority has to be altered.
+        a, b, c, d, e, f = ({'prio': 1}, {'prio': 2}, {'prio': 3}, {'prio': 4},
+                            {'prio': 5}, {'prio': 7})
         i = Heap([a, b, c, d, e, f])
         self.assertEquals(i.priorities(), [7, 4, 5, 1, 3, 2])
         i.reprioritize(a)
@@ -67,8 +76,9 @@ def test_reprioritize(self):
         self.assertEquals(i.priorities(), [7, 5, 5, 4, 3, 2])
         self.assertEquals(a, {'heappos': 1, 'prio': 5})
 
-        ## you can give any value for the desired priority change.
-        a, b, c, d, e, f = ({'prio':1},{'prio':2},{'prio':3},{'prio':4},{'prio':5},{'prio':7})
+        # you can give any value for the desired priority change.
+        a, b, c, d, e, f = ({'prio': 1}, {'prio': 2}, {'prio': 3}, {'prio': 4},
+                            {'prio': 5}, {'prio': 7})
         i = Heap([a, b, c, d, e, f])
         self.assertEquals(i.priorities(), [7, 4, 5, 1, 3, 2])
         i.reprioritize(c, 8)
@@ -76,16 +86,14 @@ def test_reprioritize(self):
         i.reprioritize(e, 15)
         self.assertEquals(i.priorities(), [20, 7, 11, 1, 4, 2])
 
-        ## a negative priority change will sink the object into the heap
+        # a negative priority change will sink the object into the heap
         i.reprioritize(e, -20)
         self.assertEquals(i.priorities(), [11, 7, 2, 1, 4, 0])
         i.reprioritize(c, -12)
         self.assertEquals(i.priorities(), [7, 4, 2, 1, -1, 0])
 
     def test_swap(self):
-        i = Heap([{'prio':1},{'prio':2},{'prio':3}])
+        i = Heap([{'prio': 1}, {'prio': 2}, {'prio': 3}])
         self.assertEquals(i.priorities(), [3, 1, 2])
         i._swap(0, 1)
         self.assertEquals(i.priorities(), [1, 3, 2])
-
-        
diff --git a/test/test_init.py b/test/test_init.py
index 923ce83..86bc568 100644
--- a/test/test_init.py
+++ b/test/test_init.py
@@ -1,6 +1,11 @@
 # coding=utf-8
 """Tests QGIS plugin init."""
 
+import os
+import unittest
+import logging
+import ConfigParser
+
 __author__ = 'Tim Sutton <tim@linfiniti.com>'
 __revision__ = '$Format:%H$'
 __date__ = '17/10/2010'
@@ -8,11 +13,6 @@
 __copyright__ = 'Copyright 2012, Australia Indonesia Facility for '
 __copyright__ += 'Disaster Reduction'
 
-import os
-import unittest
-import logging
-import ConfigParser
-
 LOGGER = logging.getLogger('QGIS')
 
 
diff --git a/test/test_qgis_environment.py b/test/test_qgis_environment.py
index 8372c55..6ae5645 100644
--- a/test/test_qgis_environment.py
+++ b/test/test_qgis_environment.py
@@ -8,11 +8,6 @@
      (at your option) any later version.
 
 """
-__author__ = 'tim@linfiniti.com'
-__date__ = '20/01/2011'
-__copyright__ = ('Copyright 2012, Australia Indonesia Facility for '
-                 'Disaster Reduction')
-
 import os
 import unittest
 from qgis.core import (
@@ -21,6 +16,12 @@
     QgsRasterLayer)
 
 from utilities import get_qgis_app
+
+__author__ = 'tim@linfiniti.com'
+__date__ = '20/01/2011'
+__copyright__ = ('Copyright 2012, Australia Indonesia Facility for '
+                 'Disaster Reduction')
+
 QGIS_APP = get_qgis_app()
 
 
diff --git a/test/test_resources.py b/test/test_resources.py
index 8511759..a432f9e 100644
--- a/test/test_resources.py
+++ b/test/test_resources.py
@@ -8,14 +8,13 @@
 
 """
 
-__author__ = 'mario@anche.no'
-__date__ = '2017-01-04'
-__copyright__ = 'Copyright 2017, Mario Frasca'
-
 import unittest
 
 from PyQt4.QtGui import QIcon
 
+__author__ = 'mario@anche.no'
+__date__ = '2017-01-04'
+__copyright__ = 'Copyright 2017, Mario Frasca'
 
 
 class DistanceMatrixToCoordsDialogTest(unittest.TestCase):
@@ -39,6 +38,3 @@ def test_icon_png(self):
     suite = unittest.makeSuite(DistanceMatrixToCoordsResourcesTest)
     runner = unittest.TextTestRunner(verbosity=2)
     runner.run(suite)
-
-
-
diff --git a/test/test_translations.py b/test/test_translations.py
index 862b342..41a883a 100644
--- a/test/test_translations.py
+++ b/test/test_translations.py
@@ -8,15 +8,14 @@
 
 """
 from utilities import get_qgis_app
+import unittest
+import os
+from PyQt4.QtCore import QCoreApplication, QTranslator
 
 __author__ = 'ismailsunni@yahoo.co.id'
 __date__ = '12/10/2011'
 __copyright__ = ('Copyright 2012, Australia Indonesia Facility for '
                  'Disaster Reduction')
-import unittest
-import os
-
-from PyQt4.QtCore import QCoreApplication, QTranslator
 
 QGIS_APP = get_qgis_app()
 
diff --git a/test/test_utils.py b/test/test_utils.py
index 63e1a69..3e50c15 100644
--- a/test/test_utils.py
+++ b/test/test_utils.py
@@ -2,6 +2,7 @@
 
 from ghini_tree_position import almost_parallel, normalize
 
+
 class UtilsTest(unittest.TestCase):
     def test_normalize_null(self):
         null_vector = (0, 0, 0)
@@ -13,28 +14,28 @@ def test_normalize_not_null(self):
         self.assertFalse(any(normalize(vector) - expected))
 
     def test_almost_parallel_vectors_not(self):
-        u, v = [1,0,0], [0,1,0]
+        u, v = [1, 0, 0], [0, 1, 0]
         self.assertFalse(almost_parallel(u, v))
 
     def test_almost_parallel_matrix_not(self):
         import numpy as np
-        A = np.array([[1,0,0],[0,1,0]])
+        A = np.array([[1, 0, 0], [0, 1, 0]])
         self.assertFalse(almost_parallel(A))
 
     def test_almost_parallel_vectors_precisely(self):
         import numpy as np
-        A = np.array([[1,1,0],[2,2,0]])
+        A = np.array([[1, 1, 0], [2, 2, 0]])
         self.assertTrue(almost_parallel(A))
 
     def test_almost_parallel_matrix_almost(self):
         import numpy as np
-        A = np.array([[1,0,0],[1999,1,-1]])
+        A = np.array([[1, 0, 0], [1999, 1, -1]])
         self.assertTrue(almost_parallel(A))
 
     def test_almost_parallel_vectors_precisely(self):
-        u, v = [1,1,0],[2,2,0]
+        u, v = [1, 1, 0], [2, 2, 0]
         self.assertTrue(almost_parallel(u, v))
 
     def test_almost_parallel_vectors_almost(self):
-        u, v = [1,0,0], [1999,1,-1]
+        u, v = [1, 0, 0], [1999, 1, -1]
         self.assertTrue(almost_parallel(u, v))
diff --git a/test/utilities.py b/test/utilities.py
index 0f4d965..33ac77c 100644
--- a/test/utilities.py
+++ b/test/utilities.py
@@ -34,7 +34,7 @@ def get_qgis_app():
 
     if QGIS_APP is None:
         gui_flag = True  # All test will run qgis in gui mode
-        #noinspection PyPep8Naming
+        # noinspection PyPep8Naming
         QGIS_APP = QgsApplication(sys.argv, gui_flag)
         # Make sure QGIS_PREFIX_PATH is set in your env if needed!
         QGIS_APP.initQgis()
@@ -43,19 +43,19 @@ def get_qgis_app():
 
     global PARENT  # pylint: disable=W0603
     if PARENT is None:
-        #noinspection PyPep8Naming
+        # noinspection PyPep8Naming
         PARENT = QtGui.QWidget()
 
     global CANVAS  # pylint: disable=W0603
     if CANVAS is None:
-        #noinspection PyPep8Naming
+        # noinspection PyPep8Naming
         CANVAS = QgsMapCanvas(PARENT)
         CANVAS.resize(QtCore.QSize(400, 400))
 
     global IFACE  # pylint: disable=W0603
     if IFACE is None:
         # QgisInterface is a stub implementation of the QGIS plugin interface
-        #noinspection PyPep8Naming
+        # noinspection PyPep8Naming
         IFACE = QgisInterface(CANVAS)
 
     return QGIS_APP, CANVAS, IFACE, PARENT