code: def test_dtypes_timedeltas(self):
      df = DataFrame(
          {
              "A": Series(date_range("2012-1-1", periods=3, freq="D")),
              "B": Series([timedelta(days=i) for i in range(3)]),
          }
      )
      result = df.dtypes
      expected = Series(
          [np.dtype("datetime64[ns]"), np.dtype("timedelta64[ns]")],
          index=list("AB"),
      )
      tm.assert_series_equal(result, expected)
  
      df["C"] = df["A"] + df["B"]
      result = df.dtypes
      expected = Series(
          [
              np.dtype("datetime64[ns]"),
              np.dtype("timedelta64[ns]"),
              np.dtype("datetime64[ns]"),
          ],
          index=list("ABC"),
      )
      tm.assert_series_equal(result, expected)
  
      # mixed int types
      df["D"] = 1
      result = df.dtypes
      expected = Series(
          [
              np.dtype("datetime64[ns]"),
              np.dtype("timedelta64[ns]"),
              np.dtype("datetime64[ns]"),
              np.dtype("int64"),
          ],
          index=list("ABCD"),
      )
      tm.assert_series_equal(result, expected)
  
file_path: pandas/pandas/tests/frame/methods/test_dtypes.py
imports: from datetime import timedelta
  import numpy
  import pytest
  from pandas.core.dtypes.dtypes import DatetimeTZDtype
  import pandas
  from pandas import DataFrame, Series, date_range, option_context
  import pandas._testing
label_desc: Use image node_id 6 for calling the TestDataFrameDataTypes obj's underlying member method code with example usage: obj.test_dtypes_timedeltas() without return types