diff --git a/examples/range_example.py b/examples/range_example.py
index 4110562..8228d81 100644
--- a/examples/range_example.py
+++ b/examples/range_example.py
@@ -36,4 +36,4 @@
 
 # dataframe.info()
 # dataframe.memory_usage(deep=True)
-# .set_index(['1','2'], inplace=True)
\ No newline at end of file
+# .set_index(['1', '2'], inplace=True)
diff --git a/examples/shortest_path_example.py b/examples/shortest_path_example.py
index c53de6e..0b73fe2 100644
--- a/examples/shortest_path_example.py
+++ b/examples/shortest_path_example.py
@@ -50,7 +50,7 @@
 
 net.set(pd.Series(net.node_ids))
 s = net.aggregate(10000, type='count')
-connected_nodes = s[s==477]
+connected_nodes = s[s == 477]
 
 n = 10000
 nodes_a = np.random.choice(connected_nodes.index, n)
@@ -60,19 +60,19 @@
 print(nodes_a[0])
 print(nodes_b[0])
 
-print(net.shortest_path(nodes_a[0],nodes_b[0]))
-print(net.shortest_path_length(nodes_a[0],nodes_b[0]))
+print(net.shortest_path(nodes_a[0], nodes_b[0]))
+print(net.shortest_path_length(nodes_a[0], nodes_b[0]))
 
 print('Shortest path 2:')
 print(nodes_a[1])
 print(nodes_b[1])
 
-print(net.shortest_path(nodes_a[1],nodes_b[1]))
-print(net.shortest_path_length(nodes_a[1],nodes_b[1]))
+print(net.shortest_path(nodes_a[1], nodes_b[1]))
+print(net.shortest_path_length(nodes_a[1], nodes_b[1]))
 
 print('Repeat with vectorized calculations:')
-print(net.shortest_paths(nodes_a[0:2],nodes_b[0:2]))
-print(net.shortest_path_lengths(nodes_a[0:2],nodes_b[0:2]))
+print(net.shortest_paths(nodes_a[0:2], nodes_b[0:2]))
+print(net.shortest_path_lengths(nodes_a[0:2], nodes_b[0:2]))
 
 # Performance comparison
 print('Performance comparison for 10k distance calculations:')
diff --git a/pandana/network.py b/pandana/network.py
index fe3086c..6842edd 100644
--- a/pandana/network.py
+++ b/pandana/network.py
@@ -284,8 +284,8 @@ def shortest_path_length(self, node_a, node_b, imp_name=None):
 
         if len == 4294967.295:
             warnings.warn(
-            "Unsigned integer: shortest path distance is trying to be calculated between\
-            external %s and %s unconntected nodes"%(node_a, node_b)
+                "Unsigned integer: shortest path distance is trying to be calculated between\
+                external %s and %s unconntected nodes" % (node_a, node_b)
             )
 
         return len
@@ -329,11 +329,11 @@ def shortest_path_lengths(self, nodes_a, nodes_b, imp_name=None):
         lens = self.net.shortest_path_distances(nodes_a_idx, nodes_b_idx, imp_num)
 
         if 4294967.295 in lens:
-             unconnected_idx = [i for i,v in enumerate(lens) if v == 4294967.295]
-             unconnected_nodes = [(nodes_a[i],nodes_b[i]) for i in unconnected_idx]
-             warnings.warn(
-             "Unsigned integer: shortest path distance is trying to be calculated \
-             between the following external unconnected nodes: %s"%(unconnected_nodes))
+            unconnected_idx = [i for i, v in enumerate(lens) if v == 4294967.295]
+            unconnected_nodes = [(nodes_a[i], nodes_b[i]) for i in unconnected_idx]
+            warnings.warn(
+                "Unsigned integer: shortest path distance is trying to be calculated \
+                between the following external unconnected nodes: %s" % (unconnected_nodes))
 
         return lens
 
diff --git a/pandana/utils.py b/pandana/utils.py
index b3ef06f..c2507c1 100644
--- a/pandana/utils.py
+++ b/pandana/utils.py
@@ -26,9 +26,10 @@ def reindex(series1, series2):
                   how="left")
     return df.right
 
+
 def adjacency_matrix(edges_df, plot_matrix=False):
     df = pd.crosstab(edges_df['from'], edges_df['to'])
     idx = df.columns.union(df.index)
-    df = df.reindex(index = idx, columns=idx, fill_value=0)
+    df = df.reindex(index=idx, columns=idx, fill_value=0)
 
     return df
diff --git a/setup.py b/setup.py
index 4aba91e..af42b2b 100644
--- a/setup.py
+++ b/setup.py
@@ -7,7 +7,7 @@
 
 
 ###############################################
-## Building the C++ extension
+# Building the C++ extension
 ###############################################
 
 extra_compile_args = ["-w", "-std=c++11", "-O3"]
@@ -77,20 +77,20 @@
 
 
 cyaccess = Extension(
-        name='pandana.cyaccess',
-        sources=[
-            'src/accessibility.cpp',
-            'src/graphalg.cpp',
-            'src/cyaccess.pyx',
-            'src/contraction_hierarchies/src/libch.cpp'],
-        language='c++',
-        include_dirs=['.', np.get_include()],
-        extra_compile_args=extra_compile_args,
-        extra_link_args=extra_link_args)
+    name='pandana.cyaccess',
+    sources=[
+        'src/accessibility.cpp',
+        'src/graphalg.cpp',
+        'src/cyaccess.pyx',
+        'src/contraction_hierarchies/src/libch.cpp'],
+    language='c++',
+    include_dirs=['.', np.get_include()],
+    extra_compile_args=extra_compile_args,
+    extra_link_args=extra_link_args)
 
 
 ###############################################
-## Standard setup
+# Standard setup
 ###############################################
 
 version = "0.7"