def METHOD_NAME(T1 : RigidTransform, T2 : RigidTransform) -> RigidTransform:
    """Composes two transformations."""
    if len(T1) != 2: raise ValueError("T1 is not a transform")
    if len(T2) != 2: raise ValueError("T2 is not a transform (did you mean to use apply())?")
    (R1,t1) = T1
    (R2,t2) = T2
    R = so3.METHOD_NAME(R1,R2)
    t = vectorops.add(so3.apply(R1,t2),t1)
    return (R,t)