docs: def get_vertex_obj_from_pathway(self, pathway):
          """Get the vertex object that corresponds to a pathway name
  
          Parameters
          -----------
          pathway : str
  
          Returns
          -----------
          Vertex|None, the Vertex obj if the pathway is in this network
          """
          if pathway in self.pathways:
              vertex_id = self.pathways[pathway]
              return self.vertices[vertex_id]
          else:
              return None