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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 frame_from_fsnative(arg):
 """Takes item from argv and returns ascii native str or raises ValueError. """


    assert isinstance(arg, fsnative)

    text = fsn2text(arg, strict=True)
    if PY2:
        return text.encode("ascii")
    else:
        return text.encode("ascii").decode("ascii")