code: def df2():
      return DataFrame(
          {
              "outer": [1, 1, 1, 1, 1, 1, 2, 2, 3, 3, 3, 3],
              "inner": [1, 2, 2, 3, 3, 4, 2, 3, 1, 1, 2, 3],
              "v2": np.linspace(10, 11, 12),
          }
      )
  
file_path: pandas/pandas/tests/reshape/merge/test_merge_index_as_string.py
imports: import numpy
  import pytest
  from pandas import DataFrame
  import pandas._testing
label_desc: Use image node_id 2 for calling a global function with example usage: df2() and returns: DataFrame