code: def test_example_proto_coder_picklable(self):
      encode_case = _maybe_extend_encode_case_with_ragged(
          _ENCODE_CASES["multiple_columns"]
      )
      schema = schema_utils.schema_from_feature_spec(
          encode_case["feature_spec"]
      )
      coder = example_proto_coder.ExampleProtoCoder(schema)
      ascii_proto = encode_case["ascii_proto"]
      instance = encode_case["instance"]
      serialized_proto = _ascii_to_binary(ascii_proto)
      for _ in range(2):
          coder = pickle.loads(pickle.dumps(coder))
          self.assertSerializedProtosEqual(
              coder.encode(instance), serialized_proto
          )
  
imports: import copy
  import os
  import pickle
  import sys
  from absl import flags
  import numpy
  import tensorflow
  from tensorflow_transform.coders import example_proto_coder
  from tensorflow_transform import test_case
  from tensorflow_transform.tf_metadata import schema_utils
  from google.protobuf.internal import api_implementation
  from google.protobuf import text_format
label_desc: Use image node_id 6 for calling the ExampleProtoCoderTest obj's underlying member method code with example usage: obj.test_example_proto_coder_picklable() without return types