def del_edge(self, edge, double=False):
(left_entity, right_entity) = edge<EOL>self[left_entity].pop(right_entity)<EOL>if double:<EOL><INDENT>self.del_edge((edge[<NUM_LIT:1>], edge[<NUM_LIT:0>]))<EOL><DEDENT>
Removes an edge from the ``DictGraph``. An edge is a pair of **node 
objects**. The **node objects** are not removed from the ``DictGraph``.

Arguments:

  - edge(``tuple``) An ordered pair of **node objects**. The edge is 
    assumed to have a direction from the first to the second **node 
    object**.
  - double(``bool``) [default: ``False```] If ``True`` the the reverse
    edge is also removed.