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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 is_subdomain_missing_zonefiles_record(rec):
 """ Does a given parsed zone file TXT record encode a missing-zonefile vector? Return True if so Return False if not """

    if rec['name'] != SUBDOMAIN_TXT_RR_MISSING:
        return False

    txt_entry = rec['txt']
    if isinstance(txt_entry, list):
        return False

    missing = txt_entry.split(',')
    try:
        for m in missing:
            m = int(m)
    except ValueError:
        return False

    return True