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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 cyvcf_add_filter(rec, name):
 """Add a FILTER value to a cyvcf2 record """

    if rec.FILTER:
        filters = rec.FILTER.split(";")
    else:
        filters = []
    if name not in filters:
        filters.append(name)
        rec.FILTER = filters
    return rec