class_docstr: A collection of functions to be tested
class_docstr_tok: ["A","collection","of","functions","to","be","tested"]
code: def func_real(be, x0, x1, x2, x3, x4):
      return (
          x1
          + be.absolute(x2 + x3)
          + x4
          - (x1 + be.square(x2 + x3) + x4)
      )
  
file_path: neon/tests/test_backend_autodiff.py
imports: from builtins import zip
  import itertools
  import numpy
  from neon import NervanaObject
  from neon.backends.autodiff import Autodiff
  from utils import call_func, gen_backend_tensors, tensors_allclose
  import pytest
label_desc: Use image node_id 2 for calling the Funcs obj's underlying member method code with example usage: obj.func_real(be, x0, x1, x2, x3, x4) and returns: unknown