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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def pts_shift(pts=[], shift=[0.0, 0.0]):
    '''Return given points shifted in N dimensions.
    '''
    assert isinstance(pts, list) and len(pts) > 0
    l_pt_prev = None
    for pt in pts:
        assert isinstance(pt, tuple)
        l_pt = len(pt)
        assert l_pt > 1
        for i in pt:
            assert isinstance(i, float)
        if l_pt_prev is not None:
            assert l_pt == l_pt_prev
        l_pt_prev = l_pt
    assert isinstance(shift, list)
    l_sh = len(shift)
    assert l_sh == l_pt
    for i in shift:
        assert isinstance(i, float)

    return [pt_shift(pt, shift) for pt in pts]