code: def does_not_contain(self, *items):
          
          if len(items) == 0:
              raise ValueError('one or more args must be given')
          elif len(items) == 1:
              if items[0] in self.val:
                  self._err('Expected <%s> to not contain item <%s>, but did.' % (self.val, items[0]))
          else:
              found = []
              for i in items:
                  if i in self.val:
                      found.append(i)
              if found:
                  self._err('Expected <%s> to not contain items %s, but did contain %s.' % (self.val, self._fmt_items(items), self._fmt_items(found)))
          return self
docs: Asserts that val does not contain the given item or items.