code: def test_reduce(string_series):
      # reductions with named functions
      result = string_series.agg(["sum", "mean"])
      expected = Series(
          [string_series.sum(), string_series.mean()],
          ["sum", "mean"],
          name=string_series.name,
      )
      tm.assert_series_equal(result, expected)
  
imports: import numpy
  import pytest
  import pandas
  from pandas import DataFrame, Index, MultiIndex, Series, concat, date_range, timedelta_range
  import pandas._testing
  from pandas.tests.apply.common import series_transform_kernels
label_desc: Use image node_id 27 for calling a global function with example usage: test_reduce(string_series) without return types