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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 to_content_range_header(self, length):
 """Converts the object into `Content-Range` HTTP header, based on given length """

        range_for_length = self.range_for_length(length)
        if range_for_length is not None:
            return "%s %d-%d/%d" % (
                self.units,
                range_for_length[0],
                range_for_length[1] - 1,
                length,
            )
        return None