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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 has_chess960_castling_rights(self) -> bool: """ Checks if there are castling rights that are only possible in Chess960. """

        # Get valid Chess960 castling rights.
        chess960 = self.chess960
        self.chess960 = True
        castling_rights = self.clean_castling_rights()
        self.chess960 = chess960

        # Standard chess castling rights can only be on the standard
        # starting rook squares.
        if castling_rights & ~BB_CORNERS:
            return True

        # If there are any castling rights in standard chess, the king must be
        # on e1 or e8.
        if castling_rights & BB_RANK_1 and not self.occupied_co[WHITE] & self.kings & BB_E1:
            return True
        if castling_rights & BB_RANK_8 and not self.occupied_co[BLACK] & self.kings & BB_E8:
            return True

        return False