code: def _test() -> None:
      import sys
      import doctest
      from pyspark.sql import SparkSession as PySparkSession
      import pyspark.sql.connect.streaming.readwriter
  
      globs = pyspark.sql.connect.readwriter.__dict__.copy()
  
      globs["spark"] = (
          PySparkSession.builder.appName(
              "sql.connect.streaming.readwriter tests"
          )
          .remote("local[4]")
          .getOrCreate()
      )
  
      (failure_count, test_count) = doctest.testmod(
          pyspark.sql.connect.streaming.readwriter,
          globs=globs,
          optionflags=doctest.ELLIPSIS
          | doctest.NORMALIZE_WHITESPACE
          | doctest.IGNORE_EXCEPTION_DETAIL,
      )
  
      globs["spark"].stop()
  
      if failure_count:
          sys.exit(-1)
  
imports: from pyspark.sql.connect.utils import check_dependencies
  import sys
  import pickle
  from typing import cast, overload, Callable, Dict, List, Optional, TYPE_CHECKING, Union
  from pyspark.serializers import CloudPickleSerializer
  from pyspark.sql.connect.plan import DataSource, LogicalPlan, Read, WriteStreamOperation
  import pyspark.sql.connect.proto
  from pyspark.sql.connect.readwriter import OptionUtils, to_str
  from pyspark.sql.connect.streaming.query import StreamingQuery
  from pyspark.sql.streaming.readwriter import DataStreamReader, DataStreamWriter
  from pyspark.sql.connect.utils import get_python_ver
  from pyspark.sql.types import Row, StructType
  from pyspark.errors import PySparkTypeError, PySparkValueError, PySparkPicklingError
label_desc: Use image node_id 1 for calling a global function with example usage: _test() without return types