code: def test_round_invalid(self, freq, error_msg):
      dti = date_range("20130101 09:10:11", periods=5)
      dti = dti.tz_localize("UTC").tz_convert("US/Eastern")
      with pytest.raises(ValueError, match=error_msg):
          dti.round(freq)
  
file_path: pandas/pandas/tests/indexes/datetimes/methods/test_round.py
imports: import pytest
  from pandas._libs.tslibs import to_offset
  from pandas._libs.tslibs.offsets import INVALID_FREQ_ERR_MSG
  from pandas import DatetimeIndex, Timestamp, date_range
  import pandas._testing
label_desc: Use image node_id 2 for calling the TestDatetimeIndexRound obj's underlying member method code with example usage: obj.test_round_invalid(freq, error_msg) without return types