code: def test_groupby_multi_timezone(self):
      # combining multiple / different timezones yields UTC
      df = DataFrame(
          {
              "value": range(5),
              "date": [
                  "2000-01-28 16:47:00",
                  "2000-01-29 16:48:00",
                  "2000-01-30 16:49:00",
                  "2000-01-31 16:50:00",
                  "2000-01-01 16:50:00",
              ],
              "tz": [
                  "America/Chicago",
                  "America/Chicago",
                  "America/Los_Angeles",
                  "America/Chicago",
                  "America/New_York",
              ],
          }
      )
  
      result = df.groupby("tz", group_keys=False).date.apply(
          lambda x: pd.to_datetime(x).dt.tz_localize(x.name)
      )
  
      expected = Series(
          [
              Timestamp(
                  "2000-01-28 16:47:00-0600", tz="America/Chicago"
              ),
              Timestamp(
                  "2000-01-29 16:48:00-0600", tz="America/Chicago"
              ),
              Timestamp(
                  "2000-01-30 16:49:00-0800", tz="America/Los_Angeles"
              ),
              Timestamp(
                  "2000-01-31 16:50:00-0600", tz="America/Chicago"
              ),
              Timestamp(
                  "2000-01-01 16:50:00-0500", tz="America/New_York"
              ),
          ],
          name="date",
          dtype=object,
      )
      tm.assert_series_equal(result, expected)
  
      tz = "America/Chicago"
      res_values = df.groupby("tz").date.get_group(tz)
      result = pd.to_datetime(res_values).dt.tz_localize(tz)
      exp_values = Series(
          [
              "2000-01-28 16:47:00",
              "2000-01-29 16:48:00",
              "2000-01-31 16:50:00",
          ],
          index=[0, 1, 3],
          name="date",
      )
      expected = pd.to_datetime(exp_values).dt.tz_localize(tz)
      tm.assert_series_equal(result, expected)
  
imports: from datetime import datetime, timedelta
  import numpy
  import pytest
  import pytz
  import pandas
  from pandas import DataFrame, DatetimeIndex, Index, MultiIndex, Series, Timestamp, date_range, offsets
  import pandas._testing
  from pandas.core.groupby.grouper import Grouper
  from pandas.core.groupby.ops import BinGrouper
label_desc: Use image node_id 12 for calling the TestGroupBy obj's underlying member method code with example usage: obj.test_groupby_multi_timezone() without return types