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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 _time_to_datetime(value):
 """Convert a time to a datetime for Cloud Datastore storage. Args: value: A datetime.time object. Returns: A datetime object with date set to 1970-01-01. """

  if not isinstance(value, datetime.time):
    raise TypeError('Cannot convert to datetime expected time value; '
                    'received %s' % value)
  return datetime.datetime(1970, 1, 1,
                           value.hour, value.minute, value.second,
                           value.microsecond)