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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 build_profile_variant(variant):
 """Returns a ProfileVariant object Args: variant (cyvcf2.Variant) Returns: variant (models.ProfileVariant) """


    chrom = variant.CHROM
    if chrom.startswith(('chr', 'CHR', 'Chr')):
        chrom = chrom[3:]

    pos = int(variant.POS)

    variant_id = get_variant_id(variant)

    ref = variant.REF
    alt = variant.ALT[0]

    maf = get_maf(variant)

    profile_variant = ProfileVariant(
        variant_id=variant_id,
        chrom=chrom,
        pos=pos,
        ref=ref,
        alt=alt,
        maf=maf,
        id_column = variant.ID
    )

    return profile_variant