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"""The synchronized Queue from the standard lib with a peek method"""

import Queue

class PQueue(Queue.Queue):
    
    def peek(self):
        if self._empty():
            raise Queue.Empty
        return self.queue[0]

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"""The synchronized Queue from the standard lib with a peek method"""

import Queue

class PQueue(Queue.Queue):

    def peek(self, block=True, timeout=None):
        """Return but do not remove an item from the queue.

        If optional args 'block' is true and 'timeout' is None (the default),
        block if necessary until an item is available. If 'timeout' is
        a positive number, it blocks at most 'timeout' seconds and raises
        the Empty exception if no item was available within that time.
        Otherwise ('block' is false), return an item if one is immediately
        available, else raise the Empty exception ('timeout' is ignored
        in that case).
        """
        self.not_empty.acquire()
        try:
            if not block:
                if self._empty():
                    raise Empty
            elif timeout is None:
                while self._empty():
                    self.not_empty.wait()
            else:
                if timeout < 0:
                    raise ValueError("'timeout' must be a positive number")
                endtime = _time() + timeout
                while self._empty():
                    remaining = endtime - _time()
                    if remaining <= 0.0:
                        raise Empty
                    self.not_empty.wait(remaining)
            item = self._peek()
            self.not_full.notify()
            return item
        finally:
            self.not_empty.release()
            
    def _peek(self):
        return self.queue[0]

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if q.peek() == x:
   return q.get()