code: def put_same_datetime(G, att_name):
      for e in G.edges(data=True):
          e[2][att_name] = datetime(2015, 1, 1)
      return G
  
imports: from datetime import date, datetime, timedelta
  import networkx
  from networkx.algorithms import isomorphism
label_desc: Use image node_id 3 for calling a global function with example usage: put_same_datetime(G, att_name) and returns: G