def METHOD_NAME(self, valid_metadata: pd.DataFrame):
    metadata = valid_metadata.copy()
    strains = ['SEQ_1', 'SEQ_3', 'SEQ_5']
    group_by_strain = augur.filter.subsample.get_groups_for_subsampling(strains, metadata)
    assert group_by_strain == {
        'SEQ_1': ('_dummy',),
        'SEQ_3': ('_dummy',),
        'SEQ_5': ('_dummy',)
    }