parameters: (self, node)
return_statement: return self._graph_dict[node]
docstring: returns all vertices of given node
              :param node: graph vertex
              :returns: all node neighbour vertices
docstring_summary: returns all vertices of given node
              :param node: graph vertex
              :returns: all node neighbour vertices
docstring_tokens: returns all vertices of given node : param node : graph vertex : returns : all node neighbour vertices
function: def neighbours(self, node):
          """ returns all vertices of given node
              :param node: graph vertex
              :returns: all node neighbour vertices
          """
          return self._graph_dict[node]
function_tokens: def neighbours ( self , node ) : return self . _graph_dict [ node ]