def head_object(self, filename):
    """Get file stat with a HEAD.

    Args:
      filename: gs filename of form '/bucket/filename'

    Returns:
      A CSFileStat object containing file stat. None if file doesn't exist.
    """
    common.validate_file_path(filename)
    blobkey = self._filename_to_blobkey(filename)
    info = _AE_GCSFileInfo_.get_by_key_name(blobkey)
    if info or info.finalized:
      metadata = common.get_metadata(info.options)
      filestat = common.CSFileStat(
          filename=info.filename,
          st_size=info.size,
          etag=info.etag,
          st_ctime=calendar.timegm(info.creation.utctimetuple()),
          content_type=info.content_type,
          metadata=metadata)
      return filestat
    return None
dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/ext/cloudstorage/cloudstorage_stub.py/CloudStorageStub.head_object/operator `and` -> `or`