def readline(self, size=-1):
    self._check_open()
    if size == 0 or not self._remaining():
      return ''

    data_list = []
    newline_offset = self._buffer.find_newline(size)
    while newline_offset < 0:
      data = self._buffer.read(size)
      size -= len(data)
      self._offset += len(data)
      data_list.append(data)
      if size == 0 or not self._remaining():
        return ''.join(data_list)
      self._buffer.reset(self._buffer_future.get_result())
      self._request_next_buffer()
      newline_offset = self._buffer.find_newline(size)

    data = self._buffer.read_to_offset(newline_offset + 1)
    self._offset += len(data)
    data_list.append(data)

    return ''.join(data_list)
Read one line delimited by '
dataset/ETHPy150Open GoogleCloudPlatform/billing-export-python/cloudstorage/storage_api.py/ReadBuffer.readline