keras/src/layers/preprocessing/random_rotation.py/RandomRotation/_set_factor
class RandomRotation:    def _set_factor(self, factor):
        if isinstance(factor, (tuple, list)):
            if len(factor) != 2:
                raise ValueError(
                    self._FACTOR_VALIDATION_ERROR + f"Received: factor={factor}"
                )
            self._check_factor_range(factor[0])
            self._check_factor_range(factor[1])
            self._factor = sorted(factor)
        elif isinstance(factor, (int, float)):
            self._check_factor_range(factor)
            factor = abs(factor)
            self._factor = [-factor, factor]
        else:
            raise ValueError(
                self._FACTOR_VALIDATION_ERROR + f"Received: factor={factor}"
            )