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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 liftover(pass_pos, matures):
 """Make position at precursor scale"""

    fixed_pos = []
    _print_header(pass_pos)
    for pos in pass_pos:
        mir = pos["mature"]
        db_pos = matures[pos["chrom"]]
        mut = _parse_mut(pos["sv"])
        print([db_pos[mir], mut, pos["sv"]])
        pos['pre_pos'] = db_pos[mir][0] + mut[1] - 1
        pos['nt'] = list(mut[0])
        fixed_pos.append(pos)
        print_vcf(pos)
    return fixed_pos