code: def test_extension_dtypes(self):
      pdf = pd.DataFrame(
          {
              "a": pd.Series([1, 2, None, 4], dtype="Int8"),
              "b": pd.Series([1, None, None, 4], dtype="Int16"),
              "c": pd.Series([1, 2, None, None], dtype="Int32"),
              "d": pd.Series([None, 2, None, 4], dtype="Int64"),
          }
      )
      psdf = ps.from_pandas(pdf)
  
      self.assert_eq(psdf, pdf)
      self.assert_eq(psdf + psdf, pdf + pdf)
  
imports: from datetime import datetime, timedelta
  import unittest
  import numpy
  import pandas
  from pyspark import pandas
  from pyspark.pandas.typedef.typehints import extension_dtypes_available, extension_float_dtypes_available, extension_object_dtypes_available
  from pyspark.pandas.utils import is_testing
  from pyspark.testing.pandasutils import ComparisonTestBase
  from pyspark.testing.sqlutils import SQLTestUtils
label_desc: Use image node_id 6 for calling the FrameConstructorMixin obj's underlying member method code with example usage: obj.test_extension_dtypes() without return types