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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 padFrameRange(frange, zfill):
 """ Return the zero-padded version of the frame range string. Args: frange (str):
 a frame range to test zfill (int):
 Returns: str: """

        def _do_pad(match):
            """
            Substitutes padded for unpadded frames.
            """
            result = list(match.groups())
            result[1] = pad(result[1], zfill)
            if result[4]:
                result[4] = pad(result[4], zfill)
            return ''.join((i for i in result if i))
        return PAD_RE.sub(_do_pad, frange)