code: def test_typical_usecase():
      df = pd.DataFrame(
          [{"var1": "a,b,c", "var2": 1}, {"var1": "d,e,f", "var2": 2}],
          columns=["var1", "var2"],
      )
      exploded = df.var1.str.split(",").explode()
      result = df[["var2"]].join(exploded)
      expected = pd.DataFrame(
          {"var2": [1, 1, 1, 2, 2, 2], "var1": list("abcdef")},
          columns=["var2", "var1"],
          index=[0, 0, 0, 1, 1, 1],
      )
      tm.assert_frame_equal(result, expected)
  
file_path: pandas/pandas/tests/series/methods/test_explode.py
imports: import numpy
  import pytest
  import pandas
  import pandas._testing
label_desc: Use image node_id 9 for calling a global function with example usage: test_typical_usecase() without return types