docstr: Add many graphs to this GraphML document.
docstr_tok: ["Add","many","graphs","to","this","GraphML","document","."]
code: def add_graphs(self, graph_list):
      """Add many graphs to this GraphML document."""
      for G in graph_list:
          self.add_graph_element(G)
  
imports: import warnings
  from collections import defaultdict
  import networkx
  from networkx.utils import open_file
label_desc: Use image node_id 10 for calling the GraphMLWriter obj's underlying member method code with example usage: obj.add_graphs(graph_list) without return types