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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 _date_to_datetime(value):
 """Convert a date to a datetime for Cloud Datastore storage. Args: value: A datetime.date object. Returns: A datetime object with time set to 0:00. """

  if not isinstance(value, datetime.date):
    raise TypeError('Cannot convert to datetime expected date value; '
                    'received %s' % value)
  return datetime.datetime(value.year, value.month, value.day)