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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 _pprint_line(line, annotations=None, annotation_file=None, block_length=10, blocks_per_line=6):
 """ Pretty-print one line. """

    annotations = annotations or []

    if annotation_file:
        # We just use the first chromosome defined in the BED file.
        _, chrom_iter = next(_bed_iter(annotation_file))
        annotations.append(list(chrom_iter))

    print(pprint_sequence(line, annotations=annotations,
                          block_length=block_length,
                          blocks_per_line=blocks_per_line, format=AnsiFormat))