public static Schema fromTableSchema(TableSchema tableSchema) {
    return fromTableSchema(tableSchema, SchemaConversionOptions.builder().build());
  }
@Test
  public void testFromTableSchema_map_map() {
    Schema beamSchema = BigQueryUtils.fromTableSchema(BQ_MAP_TYPE, INFER_MAPS_OPTIONS);
    assertEquals(MAP_MAP_TYPE, beamSchema);
  }