code: def test_expanding_corr_pairwise_diff_length():
      # GH 7512
      df1 = DataFrame(
          [[1, 2], [3, 2], [3, 4]],
          columns=["A", "B"],
          index=Index(range(3), name="bar"),
      )
      df1a = DataFrame(
          [[1, 2], [3, 4]],
          index=Index([0, 2], name="bar"),
          columns=["A", "B"],
      )
      df2 = DataFrame(
          [[5, 6], [None, None], [2, 1]],
          columns=["X", "Y"],
          index=Index(range(3), name="bar"),
      )
      df2a = DataFrame(
          [[5, 6], [2, 1]],
          index=Index([0, 2], name="bar"),
          columns=["X", "Y"],
      )
      result1 = df1.expanding().corr(df2, pairwise=True).loc[2]
      result2 = df1.expanding().corr(df2a, pairwise=True).loc[2]
      result3 = df1a.expanding().corr(df2, pairwise=True).loc[2]
      result4 = df1a.expanding().corr(df2a, pairwise=True).loc[2]
      expected = DataFrame(
          [[-1.0, -1.0], [-1.0, -1.0]],
          columns=["A", "B"],
          index=Index(["X", "Y"]),
      )
      tm.assert_frame_equal(result1, expected)
      tm.assert_frame_equal(result2, expected)
      tm.assert_frame_equal(result3, expected)
      tm.assert_frame_equal(result4, expected)
  
imports: import numpy
  import pytest
  from pandas import DataFrame, DatetimeIndex, Index, MultiIndex, Series, isna, notna
  import pandas._testing
label_desc: Use image node_id 33 for calling a global function with example usage: test_expanding_corr_pairwise_diff_length() without return types