docs: def make_matcher(*args, **kwargs):
      """Make a Matcher from a :ref:`message spec <message spec>`:
  
      >>> make_matcher()
      Matcher(Request())
      >>> make_matcher({'ismaster': 1}, namespace='admin')
      Matcher(Request({"ismaster": 1}, namespace="admin"))
      >>> make_matcher({}, {'_id': 1})
      Matcher(Request({}, {"_id": 1}))
  
      See more examples in the tutorial section for :ref:`Message Specs`.
      """
      if args and isinstance(args[0], Matcher):
          if args[1:] or kwargs:
              raise_args_err("can't interpret args")
          return args[0]
  
      return Matcher(*args, **kwargs)