code: def asyncPipeUniq(context=None, _INPUT=None, conf=None, **kwargs):
      
      _input = yield _INPUT
      asyncFuncs = yield asyncGetSplits(None, conf, **cdicts(opts, kwargs))
      pieces = yield asyncFuncs[0]()
      _pass = yield asyncFuncs[2]()
      _OUTPUT = _input if _pass else unique_items(_input, pieces.field)
      returnValue(_OUTPUT)
docs: An operator that asynchronously filters out non unique items according
      to the specified field. Not loopable.
  
      Parameters
      ----------
      context : pipe2py.Context object
      _INPUT : twisted Deferred iterable of items
      conf : {'field': {'type': 'text', 'value': <field to be unique>}}
  
      returns
      -------
      _OUTPUT : twisted.internet.defer.Deferred generator of unique items