def helper_radian_to_dimensionless(f, unit):
    from ..si import radian
    try:
        return ([get_converter(unit, radian)], dimensionless_unscaled)
    except UnitsError:
        raise UnitTypeError("Can only apply '{0}' function to quantities with angle units".format(f.__name__))
def helper_radian_to_dimensionless(f, unit):
    from ..si import radian
    try:
        return ([get_converter(unit, radian)], dimensionless_unscaled)
    except UnitsError:
        raise UnitTypeError("Can only apply '{0}' function to quantities with angle units".format(f.__name__))