parameters: (self, n)
docstring: Returns True if ``n`` is a node in the graph, False otherwise.
docstring_summary: Returns True if ``n`` is a node in the graph, False otherwise.
docstring_tokens: Returns True if n is a node in the graph False otherwise .
function: def __contains__(self, n):
          """Returns True if ``n`` is a node in the graph, False otherwise."""
          try:
              return n in self._node
          except TypeError:
              return False
function_tokens: def __contains__ ( self , n ) : try : return n in self . _node except TypeError : return False