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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 _get_segment(self, start, request_size, check_response=True):
 """Get a segment of the file from Google Storage. Args: start: start offset of the segment. Inclusive. Have to be within the range of the file. request_size: number of bytes to request. Have to be small enough for a single urlfetch request. May go over the logical range of the file. check_response: True to check the validity of GCS response automatically before the future returns. False otherwise. See Yields section. Yields: If check_response is True, the segment [start, start + request_size) of the file. Otherwise, a tuple. The first element is the unverified file segment. The second element is a closure that checks response. Caller should first invoke the closure before consuing the file segment. Raises: ValueError: if the file has changed while reading. """

    end = start + request_size - 1
    content_range = '%d-%d' % (start, end)
    headers = {'Range': 'bytes=' + content_range}
    status, resp_headers, content = yield self._api.get_object_async(
        self._path, headers=headers)
    def _checker():
      errors.check_status(status, [200, 206], self._path, headers,
                          resp_headers, body=content)
      self._check_etag(resp_headers.get('etag'))
    if check_response:
      _checker()
      raise ndb.Return(content)
    raise ndb.Return(content, _checker)