def METHOD_NAME(self, degree: int, mirror_from: int = None) -> None:
    """
    Specifies an angle that frames can get assigned to.
    :param degree: Angle identifier expressed in degrees.
    :type degree: int
    :param mirror_from: Other angle to copy frames from, if any.
    :type mirror_from: int
    """
    self.angles[degree] = {
        "degree": degree,
        "mirror_from": mirror_from,
    }