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system
provide example code for the following data structure: stack.
user
here is an example of a stack data structure implemented in python:

class stack:
    def __init__(self):
        self.items = []
 
    def push(self, item):
        self.items.append(item)
 
    def pop(self):
        return self.items.pop()
 
    def is_empty(self):
        return self.items == []
assistant