--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/env/lib/python3.7/site-packages/networkx/utils/contextmanagers.py	Thu May 14 14:56:58 2020 -0400
@@ -0,0 +1,31 @@
+
+from contextlib import contextmanager
+
+__all__ = [
+    'reversed',
+]
+
+
+@contextmanager
+def reversed(G):
+    """A context manager for temporarily reversing a directed graph in place.
+
+    This is a no-op for undirected graphs.
+
+    Parameters
+    ----------
+    G : graph
+        A NetworkX graph.
+    """
+    directed = G.is_directed()
+    if directed:
+        G._pred, G._succ = G._succ, G._pred
+        G._adj = G._succ
+
+    try:
+        yield
+    finally:
+        if directed:
+            # Reverse the reverse.
+            G._pred, G._succ = G._succ, G._pred
+            G._adj = G._succ