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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 normalize(body_part_tup,):
 """Normalize a tuple of BodyPart objects to a string. Normalization is done by sorting the body_parts by the Content- Disposition headers, which is typically on the form, ``form-data; name="name_of_part``. """

    return '\n\n'.join(
        [
            '{}\n\n{}'.format(
                str(p.headers[b'Content-Disposition'], p.encoding), p.text
            )
            for p in sorted(
                body_part_tup, key=lambda p: p.headers[b'Content-Disposition']
            )
        ]
    )