public SchemaMapping map(Schema arrowSchema, MessageType parquetSchema) {
    List<TypeMapping> children = map(arrowSchema.getFields(), parquetSchema.getFields());
    return new SchemaMapping(arrowSchema, parquetSchema, children);
  }
@Test
  public void testRepeatedMap() throws IOException {
    SchemaMapping map = converter.map(paperArrowSchema, Paper.schema);
    Assert.assertEquals("p, s<r<p>, r<p>>, r<s<r<s<p, p>>, p>>", toSummaryString(map));
  }