def angular_momentum(point, frame, *body):

    if not isinstance(frame, ReferenceFrame):
        raise TypeError('Please enter a valid ReferenceFrame')
    if not isinstance(point, Point):
        raise TypeError('Please specify a valid Point')
    else:
        angular_momentum_sys = Vector(0)
        for e in body:
            if isinstance(e, (RigidBody, Particle)):
                angular_momentum_sys += e.angular_momentum(point, frame)
            else:
                raise TypeError('*body must have only Particle or RigidBody')
    return angular_momentum_sys
Angular momentum of a system
dataset/ETHPy150Open sympy/sympy/sympy/physics/mechanics/functions.py/angular_momentum