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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 get_part_filenames(num_parts=None, start_num=0):
 """Get numbered PART.html filenames."""

    if num_parts is None:
        num_parts = get_num_part_files()
    return ['PART{0}.html'.format(i) for i in range(start_num+1, num_parts+1)]