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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 print_vcf(data):
 """Print vcf line following rules."""

    id_name = "."
    qual = "."
    chrom = data['chrom']
    pos = data['pre_pos']
    nt_ref = data['nt'][1]
    nt_snp = data['nt'][0]
    flt = "PASS"
    info = "ID=%s" % data['mature']
    frmt = "GT:NR:NS"
    gntp = "%s:%s:%s" % (_genotype(data), data["counts"], data["diff"])
    print("\t".join(map(str, [chrom, pos, id_name, nt_ref, nt_snp, qual, flt, info, frmt, gntp])), file=STDOUT, end="")