classQueue():'''Queue'''def__init__(self):
self.__list = []
defenqueue(self, item):'''Add an element to the queue'''
self.__list.append(item)
defdequeue(self):'''Delete an element from the queue header'''return self.__list.pop(0)
defis_empty(self):'''Determine whether queue is empty'''return self.__list == []
defsize(self):'''Returns the number of elements in the queue'''return len(self.__list)
defmain():
q1 = Queue()
q1.enqueue(1)
q1.enqueue(2)
q1.enqueue(3)
q1.enqueue(5)
print(q1.dequeue())
print(q1.dequeue())
print(q1.dequeue())
print(q1.dequeue())
if __name__ == '__main__':
main()
---------------results of enforcement----------
2143
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