code: def test_function_pointer_setter():
      new_function = function.Function(pointer)
  
      try:
          new_function.pointer = "a"
      except:
          new_function.pointer = callable
  
      assert (
          new_function.pointer.__class__.__name__
          == "builtin_function_or_method"
          or "builtin_function"
      )
  
file_path: opytimizer/tests/opytimizer/core/test_function.py
imports: import numpy
  from opytimizer.core import function
  from opytimizer.utils import constant
label_desc: Use image node_id 5 for calling a global function with example usage: test_function_pointer_setter() without return types