code: def register_data_source(
      self,
      read_func: Callable,
      partition_func: Callable = None,
      output: Union[str, StructType] = "i int, j int",
      name: str = "test",
  ):
      class TestDataSourceReader(DataSourceReader):
          def __init__(self, schema):
              self.schema = schema
  
          def partitions(self):
              if partition_func is not None:
                  return partition_func()
              else:
                  raise NotImplementedError
  
          def read(self, partition):
              return read_func(self.schema, partition)
  
      class TestDataSource(DataSource):
          @classmethod
          def name(cls):
              return name
  
          def schema(self):
              return output
  
          def reader(self, schema) -> "DataSourceReader":
              return TestDataSourceReader(schema)
  
      self.spark.dataSource.register(TestDataSource)
  
imports: import os
  import tempfile
  import unittest
  from typing import Callable, Union
  from pyspark.errors import PythonException
  from pyspark.sql.datasource import DataSource, DataSourceReader, InputPartition, DataSourceWriter, WriterCommitMessage, CaseInsensitiveDict
  from pyspark.sql.types import Row, StructType
  from pyspark.testing import assertDataFrameEqual
  from pyspark.testing.sqlutils import ReusedSQLTestCase
  from pyspark.testing.utils import SPARK_HOME
label_desc: Use image node_id 4 for calling the BasePythonDataSourceTestsMixin obj's underlying member method code with example usage: obj.register_data_source(read_func, partition_func, output, name) and returns: read_func, name, output, TestDataSourceReader, partition_func