code: def to_call_agraph(self):
          
  
          A = nx.nx_agraph.to_agraph(self.call_graph)
          A.graph_attr.update({"dpi": 227, "fontsize": 20, "fontname": "Menlo"})
          A.node_attr.update(
              {"shape": "rectangle", "color": "#650021", "style": "rounded"}
          )
          A.edge_attr.update({"color": "#650021", "arrowsize": 0.5})
          return A
docs: Build a PyGraphviz AGraph object corresponding to a call graph of
          functions.