code: def test_raises_error_if_na_in_df(df_na, df_vartypes):
      # when dataset contains na, fit method
      with pytest.raises(ValueError):
          transformer = LogCpTransformer()
          transformer.fit(df_na)
  
      # when dataset contains na, transform method
      with pytest.raises(ValueError):
          transformer = LogCpTransformer()
          transformer.fit(df_vartypes)
          transformer.transform(
              df_na[["Name", "City", "Age", "Marks", "dob"]]
          )
  
file_path: feature_engine/tests/test_transformation/test_logcp_transformer.py
imports: import pandas
  import pytest
  from sklearn.exceptions import NotFittedError
  from feature_engine.transformation import LogCpTransformer
label_desc: Use image node_id 7 for calling a global function with example usage: test_raises_error_if_na_in_df(df_na, df_vartypes) without return types