python中有栈吗

class Stack:
 def __init__(self):
 self.stack = []
 def add(self, dataval):# Use list append method to add element
 if dataval not in self.stack:
 self.stack.append(dataval)
 return True
 else:
 return False# Use peek to look at the top of the stack
 def peek(self): 
 return self.stack[0]AStack = Stack()AStack.add("Mon")AStack.add("Tue")AStack.peek()print(AStack.peek())AStack.add("Wed")AStack.add("Thu")print(AStack.peek())Python

Mon
MonShell