parameters: (self, attribute, value)
return_statement: return None
docstring: Find and return the edge with the specified attribute / value pair.
  
          @type  attribute: String
          @param attribute: Attribute name we are looking for
          @type  value:     Mixed
          @param value:     Value of attribute we are looking for
  
          @rtype:  Mixed
          @return: Edge, if attribute / value pair is matched. None otherwise.
docstring_summary: Find and return the edge with the specified attribute / value pair.
docstring_tokens: Find and return the edge with the specified attribute / value pair .
function: def find_edge (self, attribute, value):
          '''
          Find and return the edge with the specified attribute / value pair.
  
          @type  attribute: String
          @param attribute: Attribute name we are looking for
          @type  value:     Mixed
          @param value:     Value of attribute we are looking for
  
          @rtype:  Mixed
          @return: Edge, if attribute / value pair is matched. None otherwise.
          '''
  
          # if the attribute to search for is the id, simply return the edge from the internal hash.
          if attribute == "id" and self.edges.has_key(value):
              return self.edges[value]
  
          # step through all the edges looking for the given attribute/value pair.
          else:
              for edges in self.edges.values():
                  if hasattr(edge, attribute):
                      if getattr(edge, attribute) == value:
                          return edge
  
          return None
function_tokens: def find_edge ( self , attribute , value ) : # if the attribute to search for is the id, simply return the edge from the internal hash. if attribute == "id" and self . edges . has_key ( value ) : return self . edges [ value ] # step through all the edges looking for the given attribute/value pair. else : for edges in self . edges . values ( ) : if hasattr ( edge , attribute ) : if getattr ( edge , attribute ) == value : return edge return None