Author Dusty Phillips Reviewers

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 184 
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The class also has methods to check whether the 
Queue
is 
full()
or 
empty()
and 
there are a few additional methods to deal with concurrent access that we won't 
discuss here. Here is a interactive session demonstrating these principles:
>>> from queue import Queue
>>> lineup = Queue(maxsize=3)
>>> lineup.get(block=False)
Traceback (most recent call last):
File "", line 1, in
lineup.get(block=False)
File "/usr/lib64/python3.3/queue.py", line 164, in get
raise Empty
queue.Empty
>>> lineup.put("one")
>>> lineup.put("two")
>>> lineup.put("three")
>>> lineup.put("four", timeout=1)
Traceback (most recent call last):
File "", line 1, in
lineup.put("four", timeout=1)
File "/usr/lib64/python3.3/queue.py", line 144, in put
raise Full
queue.Full
>>> lineup.full()
True
>>> lineup.get()
'one'
>>> lineup.get()
'two'
>>> lineup.get()
'three'
>>> lineup.empty()
True
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Chapter 6
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 185 
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Underneath the hood, Python implements queues on top of the 
collections.deque
data structure. Deques are advanced data structures that permits efficient access to 
both ends of the collection. It provides a more flexible interface than is exposed by 
Queue
. I refer you to the Python documentation if you'd like to experiment more 
with it.
LIFO queues