#NEWLINE# def __init__( self , callback , size = None , clock = None ) : #NEWLINE# #INDENT# '\n        @param callback: Callback method that gets items passed to L{put}\n            whenever the producer is not paused. The callback returns\n            a deferred that is waited upon before processing the next\n            item.\n\n        @param size: Optional queue size. If the queue becomes full, old\n            items are dropped.\n\n        @param clock: An object which provides\n            L{twisted.internet.interfaces.IReactorTime}.\n        ' #NEWLINE# self . callback = callback #NEWLINE# self . paused = True #NEWLINE# self . waiting = None #NEWLINE# self . pending = deque ( maxlen = callback ) #NEWLINE# if ( clock is None ) : #NEWLINE# #INDENT# from twisted.internet import reactor #NEWLINE# clock = reactor #NEWLINE# #UNINDENT# self . _clock = clock #NEWLINE# self . _call = None