code: def ExecutePlan(self, req: proto.ExecutePlanRequest, metadata):
      self.req = req
      resp = proto.ExecutePlanResponse()
      resp.session_id = self._session_id
  
      pdf = pd.DataFrame(data={"col1": [1, 2]})
      schema = pa.Schema.from_pandas(pdf)
      table = pa.Table.from_pandas(pdf)
      sink = pa.BufferOutputStream()
  
      writer = pa.ipc.new_stream(sink, schema=schema)
      writer.write(table)
      writer.close()
  
      buf = sink.getvalue()
      resp.arrow_batch.data = buf.to_pybytes()
      resp.arrow_batch.row_count = 2
      return [resp]
  
imports: import unittest
  import uuid
  from collections.abc import Generator
  from typing import Optional, Any
  from pyspark.testing.connectutils import should_test_connect, connect_requirement_message
  from pyspark.testing.utils import eventually
label_desc: Use image node_id 2 for calling the MockService obj's underlying member method code with example usage: obj.ExecutePlan(req, metadata) and returns: list