code: def test_case_insensitive_grouping_column(self):
      # SPARK-31915: case-insensitive grouping column should work.
      df1 = self.spark.createDataFrame([(1, 1)], ("column", "value"))
  
      row = (
          df1.groupby("ColUmn")
          .cogroup(df1.groupby("COLUMN"))
          .applyInPandas(lambda r, l: r + l, "column long, value long")
          .first()
      )
      self.assertEqual(row.asDict(), Row(column=2, value=2).asDict())
  
      df2 = self.spark.createDataFrame([(1, 1)], ("column", "value"))
  
      row = (
          df1.groupby("ColUmn")
          .cogroup(df2.groupby("COLUMN"))
          .applyInPandas(lambda r, l: r + l, "column long, value long")
          .first()
      )
      self.assertEqual(row.asDict(), Row(column=2, value=2).asDict())
  
imports: import unittest
  from typing import cast
  from pyspark.sql.functions import array, explode, col, lit, udf, pandas_udf, sum
  from pyspark.sql.types import ArrayType, DoubleType, LongType, StructType, StructField, YearMonthIntervalType, Row
  from pyspark.sql.window import Window
  from pyspark.errors import IllegalArgumentException, PythonException
  from pyspark.testing.sqlutils import ReusedSQLTestCase, have_pandas, have_pyarrow, pandas_requirement_message, pyarrow_requirement_message
  from pyspark.testing.utils import QuietTest
label_desc: Use image node_id 34 for calling the CogroupedApplyInPandasTestsMixin obj's underlying member method code with example usage: obj.test_case_insensitive_grouping_column() without return types