code: def test_schema(self):
      table_schema = TableSchema(
          ["a", "b"], [DataTypes.INT(), DataTypes.STRING()]
      )
  
      schema = Schema().schema(table_schema)
  
      properties = schema.to_properties()
      expected = {
          "schema.0.name": "a",
          "schema.0.data-type": "INT",
          "schema.1.name": "b",
          "schema.1.data-type": "VARCHAR(2147483647)",
      }
      self.assertEqual(expected, properties)
  
imports: import collections
  import sys
  from pyflink.table.descriptors import Rowtime, Schema
  from pyflink.table.table_schema import TableSchema
  from pyflink.table.types import DataTypes
  from pyflink.testing.test_case_utils import PyFlinkTestCase
label_desc: Use image node_id 7 for calling the SchemaDescriptorTests obj's underlying member method code with example usage: obj.test_schema() without return types