code: def test_serialize_pandas_dataframes():
      pd, np = opt.pandas, opt.np
      df = pd.DataFrame(
          np.arange(20).reshape(5, 4), columns=list("ABCD")
      )
      b = restore(flatten(df))
      assert np.all(df == b)
      assert np.all(df.dtypes == b.dtypes)
  
file_path: sacred/tests/test_serializer.py
imports: import pytest
  from sacred.serializer import flatten, restore
  import sacred.optional
label_desc: Use image node_id 6 for calling a global function with example usage: test_serialize_pandas_dataframes() without return types