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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _dict_to_obj(self, d):
 """Converts a dictionary of json object to a Python object."""

    if JsonEncoder.TYPE_ID not in d:
      return d

    type_name = d.pop(JsonEncoder.TYPE_ID)
    if type_name in _TYPE_NAME_TO_DECODER:
      decoder = _TYPE_NAME_TO_DECODER[type_name]
      return decoder(d)
    else:
      raise TypeError("Invalid type %s.", type_name)