code: def _test_expect_element(self):
      set_ = {"a", "b"}
  
      @expect_element(a=set_)
      def f(a):
          return a
  
      self.assertEqual(f("a"), "a")
      self.assertEqual(f("b"), "b")
  
      with self.assertRaises(ValueError) as e:
          f("c")
  
      expected_message = (
          "{qualname}() expected a value in {set_!r}"
          " for argument 'a', but got 'c' instead."
      ).format(
          # We special-case set to show a tuple instead of the set repr.
          set_=tuple(sorted(set_)),
          qualname=qualname(f),
      )
      self.assertEqual(e.exception.args[0], expected_message)
  
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 13 for calling the PreprocessTestCase obj's underlying member method code with example usage: obj._test_expect_element() and returns: a