code: def test_format_pre_1900_dates(self):
      rng = date_range("1/1/1850", "1/1/1950", freq="YE-DEC")
      msg = "DatetimeIndex.format is deprecated"
      with tm.assert_produces_warning(FutureWarning, match=msg):
          rng.format()
      ts = Series(1, index=rng)
      repr(ts)
  
imports: from datetime import datetime, timedelta
  import numpy
  import pytest
  from pandas._config import using_pyarrow_string_dtype
  import pandas
  from pandas import Categorical, DataFrame, Index, Series, date_range, option_context, period_range, timedelta_range
  import pandas._testing
label_desc: Use image node_id 24 for calling the TestSeriesRepr obj's underlying member method code with example usage: obj.test_format_pre_1900_dates() without return types