parameters: (graph, get_edges)
return_statement: return ordered_nodes
docstring: Topologically sort based on a user provided edge definition.
  
    Args:
      graph: A list of node names.
      get_edges: A function mapping from node name to a hashable collection
                 of node names which this node has outgoing edges to.
    Returns:
      A list containing all of the node in graph in topological order.
      It is assumed that calling get_edges once for each node and caching is
      cheaper than repeatedly calling get_edges.
    Raises:
      CycleError in the event of a cycle.
    Example:
      graph = {'a': '$(b) $(c)', 'b': 'hi', 'c': '$(b)'}
      def GetEdges(node):
        return re.findall(r'\$\(([^))]\)', graph[node])
      print TopologicallySorted(graph.keys(), GetEdges)
      ==>
      ['a', 'c', b']
docstring_summary: Topologically sort based on a user provided edge definition.
docstring_tokens: Topologically sort based on a user provided edge definition .
function: def TopologicallySorted(graph, get_edges):
    """Topologically sort based on a user provided edge definition.
  
    Args:
      graph: A list of node names.
      get_edges: A function mapping from node name to a hashable collection
                 of node names which this node has outgoing edges to.
    Returns:
      A list containing all of the node in graph in topological order.
      It is assumed that calling get_edges once for each node and caching is
      cheaper than repeatedly calling get_edges.
    Raises:
      CycleError in the event of a cycle.
    Example:
      graph = {'a': '$(b) $(c)', 'b': 'hi', 'c': '$(b)'}
      def GetEdges(node):
        return re.findall(r'\$\(([^))]\)', graph[node])
      print TopologicallySorted(graph.keys(), GetEdges)
      ==>
      ['a', 'c', b']
    """
    get_edges = memoize(get_edges)
    visited = set()
    visiting = set()
    ordered_nodes = []
    def Visit(node):
      if node in visiting:
        raise CycleError(visiting)
      if node in visited:
        return
      visited.add(node)
      visiting.add(node)
      for neighbor in get_edges(node):
        Visit(neighbor)
      visiting.remove(node)
      ordered_nodes.insert(0, node)
    for node in sorted(graph):
      Visit(node)
    return ordered_nodes
function_tokens: def TopologicallySorted ( graph , get_edges ) : get_edges = memoize ( get_edges ) visited = set ( ) visiting = set ( ) ordered_nodes = [ ] def Visit ( node ) : if node in visiting : raise CycleError ( visiting ) if node in visited : return visited . add ( node ) visiting . add ( node ) for neighbor in get_edges ( node ) : Visit ( neighbor ) visiting . remove ( node ) ordered_nodes . insert ( 0 , node ) for node in sorted ( graph ) : Visit ( node ) return ordered_nodes