How to use the quantities.dimensionality.Dimensionality function in quantities

def __div__(self, other):
            assert_isinstance(other, Dimensionality)
            return self.__truediv__(other)

def __pow__(self, other):
        try:
            assert np.isscalar(other)
        except AssertionError:
            raise TypeError('exponent must be a scalar, got %r' % other)
        if other == 0:
            return Dimensionality()
        new = Dimensionality(self)
        for i in new:
            new[i] *= other
        return new

def __truediv__(self, other):
        assert_isinstance(other, Dimensionality)
        new = Dimensionality(self)
        for unit, power in other.items():
            try:
                new[unit] -= power
                if new[unit] == 0:
                    new.pop(unit)
            except KeyError:
                new[unit] = -power
        return new

def __itruediv__(self, other):
        assert_isinstance(other, Dimensionality)
        for unit, power in other.items():
            try:
                self[unit] -= power
                if self[unit] == 0:
                    self.pop(unit)
            except KeyError:
                self[unit] = -power
        return self

def copy(self):
        return Dimensionality(self)

def _d_trig(q1, out=None):
    try:
        assert q1.units == unit_registry['radian']
    except AssertionError:
        raise ValueError(
            'expected units of radians, got "%s"' % q1._dimensionality
        )
    return Dimensionality()
p_dict[np.sin] = _d_trig

def __pow__(self, other):
        try:
            assert np.isscalar(other)
        except AssertionError:
            raise TypeError('exponent must be a scalar, got %r' % other)
        if other == 0:
            return Dimensionality()
        new = Dimensionality(self)
        for i in new:
            new[i] *= other
        return new

def __array_finalize__(self, obj):
        self._dimensionality = getattr(obj, 'dimensionality', Dimensionality())

def dimensionless(value):
    """Test for dimensionlessness of input."""
    if type(value) is Quantity:
        if value.dimensionality == Dimensionality({}):
            value = value.base.item()
        else:
            raise TypeError("Score value %s must be dimensionless" % value)
    return value