code: def test_make_transformer(mode):
      def fun(x, y, m=0):
          return x + y if m == 0 else x - y
  
      tr = make_transformer(fun)
  
      tr.fit()
      res = tr.transform(7, 3, m=mode)
      assert res == (10 if mode == 0 else 4)
  
file_path: steppy/tests/test_base.py
imports: import numpy
  import pytest
  from steppy.base import Step, StepError, make_transformer, IdentityOperation
  from steppy.adapter import Adapter, E
label_desc: Use image node_id 2 for calling a global function with example usage: test_make_transformer(mode) and returns: unknown