networkx/networkx — pull request #745 by carmandrew (2012-08-02 22:21:05+00:00)
Title: Fix missing itertools dependency calling compose on a directed graph

When calling graph.compose(other_graph) and they're both directed graphs, it fails with the message

```
.../venv/lib/python2.7/site-packages/networkx/classes/function.pyc in all_neighbors(graph, node)
394 """
395 if graph.is_directed():
--> 396 values = itertools.chain.from_iterable([graph.predecessors_iter(node),
397 graph.successors_iter(node)])
398 else:

NameError: global name 'itertools' is not defined
```