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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_valid_sid_for_new_standalone(sysmeta_pyxb):
 """Assert that any SID in ``sysmeta_pyxb`` can be assigned to a new standalone object."""

    sid = d1_common.xml.get_opt_val(sysmeta_pyxb, 'seriesId')
    if not d1_gmn.app.did.is_valid_sid_for_new_standalone(sid):
        raise d1_common.types.exceptions.IdentifierNotUnique(
            0,
            'Identifier is already in use as {}. did="{}"'.format(
                d1_gmn.app.did.classify_identifier(sid), sid
            ),
            identifier=sid,
        )