code: def graph(self, as_dot=False):
          
          if not self.has_graph:
              return None
  
          if not as_dot:
              if self.graph_ is None:
                  # reads either dot format or our compact format
                  self.graph_ = read_graph_from_string(self.graph_string)
              return self.graph_
  
          if self.graph_string:
              if self.graph_string.startswith('{'):  # compact format
                  self.graph_ = read_graph_from_string(self.graph_string)
              else:
                  # already in dot format. Note that this will only happen in
                  # old rez contexts where the graph is not stored in the newer
                  # compact format.
                  return self.graph_string
  
          return write_dot(self.graph_)
docs: Get the resolve graph.
  
          Args:
              as_dot: If True, get the graph as a dot-language string. Otherwise,
                  a pygraph.digraph object is returned.
  
          Returns:
              A string or `pygraph.digraph` object, or None if there is no graph
              associated with the resolve.