'x.__rsub__(y) <=> y-x
Only `NDArray` is supported for now.
Example usage:
>>> x = mx.nd.ones((2,3))*3
>>> y = mx.nd.ones((2,3))
>>> x.__rsub__(y).asnumpy()
array([[-2., -2., -2.],
[-2., -2., -2.]], dtype=float32)'

def __rsub__(self, other):

    if isinstance(other, Number):
        return _internal._RMinusScalar(self, scalar=other)
    else:
        raise TypeError(('type    %s    not    supported' % str(type(other))))
