code: def _test_preprocess_no_processors(self, args, kwargs):
      @preprocess()
      def func(a, b, c=3):
          return a, b, c
  
      self.assertEqual(func(*args, **kwargs), (1, 2, 3))
  
imports: from operator import attrgetter
  from types import FunctionType
  from unittest import TestCase
  from nose_parameterized import parameterized
  from numpy import arange, array, dtype
  import pytz
  from six import PY3
  from catalyst.utils.preprocess import call, preprocess
  from catalyst.utils.input_validation import expect_dimensions, ensure_timezone, expect_element, expect_dtypes, expect_types, optional, optionally
label_desc: Use image node_id 5 for calling the PreprocessTestCase obj's underlying member method code with example usage: obj._test_preprocess_no_processors(args, kwargs) and returns: a,  b,  c