code: def test_where_dups():
      # GH 4550
      # where crashes with dups in index
      s1 = Series(list(range(3)))
      s2 = Series(list(range(3)))
      comb = pd.concat([s1, s2])
      result = comb.where(comb < 2)
      expected = Series(
          [0, 1, np.nan, 0, 1, np.nan], index=[0, 1, 2, 0, 1, 2]
      )
      tm.assert_series_equal(result, expected)
  
      # GH 4548
      # inplace updating not working with dups
      comb[comb < 1] = 5
      expected = Series([5, 1, 2, 5, 1, 2], index=[0, 1, 2, 0, 1, 2])
      tm.assert_series_equal(comb, expected)
  
      comb[comb < 2] += 10
      expected = Series([5, 11, 2, 5, 11, 2], index=[0, 1, 2, 0, 1, 2])
      tm.assert_series_equal(comb, expected)
  
imports: import numpy
  import pytest
  from pandas._config import using_pyarrow_string_dtype
  from pandas.core.dtypes.common import is_integer
  import pandas
  from pandas import Series, Timestamp, date_range, isna
  import pandas._testing
label_desc: Use image node_id 13 for calling a global function with example usage: test_where_dups() without return types