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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 add_headers(vcf_obj, nr_cases=None, sv=False):
 """Add loqus specific information to a VCF header Args: vcf_obj(cyvcf2.VCF) """


    vcf_obj.add_info_to_header(
        {
            'ID':"Obs",
            'Number': '1',
            'Type': 'Integer',
            'Description': "The number of observations for the variant"}
    )
    if not sv:
        vcf_obj.add_info_to_header(
            {
                'ID':"Hom",
                'Number': '1',
                'Type': 'Integer',
                'Description': "The number of observed homozygotes"}
        )
        vcf_obj.add_info_to_header(
            {
                'ID':"Hem",
                'Number': '1',
                'Type': 'Integer',
                'Description': "The number of observed hemizygotes"}
        )
    if nr_cases:
        case_header = "##NrCases={}".format(nr_cases)
        vcf_obj.add_to_header(case_header)
    # head.add_version_tracking("loqusdb", version, datetime.now().strftime("%Y-%m-%d %H:%M"))
    return