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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 part_lister(mpupload, part_number_marker=None):
 """ A generator function for listing parts of a multipart upload. """

    more_results = True
    part = None
    while more_results:
        parts = mpupload.get_all_parts(None, part_number_marker)
        for part in parts:
            yield part
        part_number_marker = mpupload.next_part_number_marker
        more_results= mpupload.is_truncated