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Solve the following problem using Python, implementing the functions described below, one line at a time
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<USER_TASK:>
Description:
 def validate_type_ac_pair(type, ac):
 """validate that accession is correct for variant type AND that accession is fully specified. """


    assert type in valid_pairs, "Unknown variant type " + type
    if valid_pairs[type].match(ac):
        return (ValidationLevel.VALID,
                "Accession ({ac}) is compatible with variant type {type}".format(ac=ac, type=type))
    elif invalid_pairs[type].match(ac):
        return (ValidationLevel.ERROR,
                "Accession ({ac}) is not compatible with variant type {type}".format(
                    ac=ac, type=type))
    else:
        return (ValidationLevel.WARNING,
                "Accession ({ac}) is not known to be compatible with variant type {type}".format(
                    ac=ac, type=type))