new_contents: import unittest
  
  class TestDicts(unittest.TestCase):
    "Testing set functions"
  
    def test_dict_keys_as_set(self):
      stacks = {
        "Jake": 10785,
        "Mitch": 5555,
        "Natalie": 400,
        "Frannie": 6005 
      }
  
      self.assertTrue("Frannie" in set(stacks))
  
subject: test in set