code: def contains_entry(self, *args, **kwargs):
          
          self._check_dict_like(self.val, check_values=False)
          entries = list(args) + [{k:v} for k,v in kwargs.items()]
          if len(entries) == 0:
              raise ValueError('one or more entry args must be given')
          missing = []
          for e in entries:
              if type(e) is not dict:
                  raise TypeError('given entry arg must be a dict')
              if len(e) != 1:
                  raise ValueError('given entry args must contain exactly one key-value pair')
              k = next(iter(e))
              if k not in self.val:
                  missing.append(e) # bad key
              elif self.val[k] != e[k]:
                  missing.append(e) # bad val
          if missing:
              self._err('Expected <%s> to contain entries %s, but did not contain %s.' % (self.val, self._fmt_items(entries), self._fmt_items(missing)))
          return self
docs: Asserts that val is a dict and contains the given entry or entries.