(self, edge, src_vertex, dest_vertex)
Draws a directed edge.

        @param edge: the edge to be drawn. Visual properties of the edge
          are defined by the attributes of this object.
        @param src_vertex: the source vertex. Visual properties are given
          again as attributes.
        @param dest_vertex: the target vertex. Visual properties are given
          again as attributes.
Draws a directed edge.
Draws a directed edge .
def draw_directed_edge(self, edge, src_vertex, dest_vertex):
        """Draws a directed edge.

        @param edge: the edge to be drawn. Visual properties of the edge
          are defined by the attributes of this object.
        @param src_vertex: the source vertex. Visual properties are given
          again as attributes.
        @param dest_vertex: the target vertex. Visual properties are given
          again as attributes.
        """
        raise NotImplementedError()
def draw_directed_edge ( self , edge , src_vertex , dest_vertex ) : raise NotImplementedError ( )