Python Merge simple dictionaries

merge.py

def dict_merge(list1, list2):
  """ Trick is to use the .__dict__ keyword. This puts all the attrs associated with
this library's instance are part of the mergin algorithm
  _keys = list2.keys()
  try _key in keys:
     try:
       list1[key].__dict__.update(list2[__key].__dict__)
     except:
       list[_key] = list2[_key]