Apply PEP8 in code

2 files changed, 18 insertions, 15 deletions

diff --git a/networkx/algorithms/components/attracting.py b/networkx/algorithms/components/attracting.py
index 9351ed00..ae805903 100644
--- a/networkx/algorithms/components/attracting.py
+++ b/networkx/algorithms/components/attracting.py
@@ -11,12 +11,13 @@
 import networkx as nx
 from networkx.utils.decorators import not_implemented_for
 
-__all__ = ['number_attracting_components', 
+__all__ = ['number_attracting_components',
            'attracting_components',
-           'is_attracting_component', 
+           'is_attracting_component',
            'attracting_component_subgraphs',
            ]
 
+
 @not_implemented_for('undirected')
 def attracting_components(G):
     """Generates a list of attracting components in `G`.
@@ -47,7 +48,7 @@ def attracting_components(G):
     See Also
     --------
     number_attracting_components
-    is_attracting_component 
+    is_attracting_component
     attracting_component_subgraphs
 
     """
@@ -57,6 +58,7 @@ def attracting_components(G):
         if cG.out_degree(n) == 0:
             yield scc[n]
 
+
 @not_implemented_for('undirected')
 def number_attracting_components(G):
     """Returns the number of attracting components in `G`.
@@ -136,7 +138,7 @@ def attracting_component_subgraphs(G, copy=True):
         A list of node-induced subgraphs of the attracting components of `G`.
 
     copy : bool
-        If copy is True, graph, node, and edge attributes are copied to the 
+        If copy is True, graph, node, and edge attributes are copied to the
         subgraphs.
 
     Raises
diff --git a/networkx/algorithms/components/biconnected.py b/networkx/algorithms/components/biconnected.py
index 6bd6aff2..53a96caf 100644
--- a/networkx/algorithms/components/biconnected.py
+++ b/networkx/algorithms/components/biconnected.py
@@ -89,7 +89,7 @@ def is_biconnected(G):
 
     """
     bcc = list(biconnected_components(G))
-    if not bcc: # No bicomponents (it could be an empty graph)
+    if not bcc:  # No bicomponents (it could be an empty graph)
         return False
     return len(bcc[0]) == len(G)
 
@@ -254,6 +254,7 @@ def biconnected_components(G):
     for comp in _biconnected_dfs(G, components=True):
         yield set(chain.from_iterable(comp))
 
+
 @not_implemented_for('directed')
 def biconnected_component_subgraphs(G, copy=True):
     """Return a generator of graphs, one graph for each biconnected component
@@ -427,8 +428,8 @@ def _biconnected_dfs(G, components=True):
     for start in G:
         if start in visited:
             continue
-        discovery = {start:0} # "time" of first discovery of node during search
-        low = {start:0}
+        discovery = {start: 0}  # time of first discovery of node during search
+        low = {start: 0}
         root_children = 0
         visited.add(start)
         edge_stack = []
@@ -440,31 +441,31 @@ def _biconnected_dfs(G, components=True):
                 if grandparent == child:
                     continue
                 if child in visited:
-                    if discovery[child] <= discovery[parent]: # back edge
-                        low[parent] = min(low[parent],discovery[child])
+                    if discovery[child] <= discovery[parent]:  # back edge
+                        low[parent] = min(low[parent], discovery[child])
                         if components:
-                            edge_stack.append((parent,child))
+                            edge_stack.append((parent, child))
                 else:
                     low[child] = discovery[child] = len(discovery)
                     visited.add(child)
                     stack.append((parent, child, iter(G[child])))
                     if components:
-                        edge_stack.append((parent,child))
+                        edge_stack.append((parent, child))
             except StopIteration:
                 stack.pop()
                 if len(stack) > 1:
                     if low[parent] >= discovery[grandparent]:
                         if components:
-                            ind = edge_stack.index((grandparent,parent))
+                            ind = edge_stack.index((grandparent, parent))
                             yield edge_stack[ind:]
-                            edge_stack=edge_stack[:ind]
+                            edge_stack = edge_stack[:ind]
                         else:
                             yield grandparent
                     low[grandparent] = min(low[parent], low[grandparent])
-                elif stack: # length 1 so grandparent is root
+                elif stack:  # length 1 so grandparent is root
                     root_children += 1
                     if components:
-                        ind = edge_stack.index((grandparent,parent))
+                        ind = edge_stack.index((grandparent, parent))
                         yield edge_stack[ind:]
         if not components:
             # root node is articulation point if it has more than 1 child