anchor.diff:  
   -define(DATAFRAME, 'pandas.core.frame.DataFrame').
   -define(SERIES, 'pandas.core.frame.Series').
  +-define(PYODBC, 'pyodbc.conn').
   
   -export([all/0, init_per_testcase/2, end_per_testcase/2]).
   -export([test_jun_pandas_read_csv/1,
  
positive.code:      test_jun_pandas_to_json,
       test_jun_pandas_to_erl,
       test_jun_pandas_bad_call,
       test_jun_pandas_to_datetime].
  
  init_per_testcase(_, _Config) ->
      % for each case start a new worker
  
negative.code:     test_jun_pandas_to_json/1,
      test_jun_pandas_to_erl/1,
      test_jun_pandas_bad_call/1,
      test_jun_pandas_to_datetime/1,
      test_jun_pandas_read_sql/1]).
  
  all() ->
      [test_jun_pandas_read_csv,
  