class_docstr: Implementation of multiple disjoint graph structure in pgl.
  
  This is a simple implementation of graph structure in pgl.
  
  Args:
      graph_list :  A list of Graph Instances
  
  Examples:
  
      .. code-block:: python
      
          batch_graph = MultiGraph([graph1, graph2, graph3])
class_docstr_tok: ["Implementation","of","multiple","disjoint","graph","structure","in","pgl",".","This","is","a","simple","implementation","of","graph","structure","in","pgl",".","Args",":","graph_list",":","A","list","of","Graph","Instances","Examples",":","..","code-block",":",":","python","batch_graph","=","MultiGraph","(","[","graph1",",","graph2",",","graph3","]",")"]
code: def __getitem__(self, index):
      return self._src_graph[index]
  
imports: import os
  import numpy
  import pickle
  import time
  import pgl.graph_kernel
  from collections import defaultdict
label_desc: Use image node_id 2 for calling the MultiGraph obj's underlying member method code with example usage: obj.__getitem__(index) and returns: self