将以上代码中的顺序栈改成循环栈

好的，以下是将顺序栈改成循环栈的代码：
class CircularStack:
def __init__(self, capacity):
self.capacity = capacity
self.stack = [None] * capacity
self.top = -1

def is_empty(self):
return self.top == -1

def is_full(self):
return (self.top + 1) % self.capacity == 0

def push(self, value):
if self.is_full():
raise Exception("Stack is full")
self.top = (self.top + 1) % self.capacity
self.stack[self.top] = value

def pop(self):
if self.is_empty():
raise Exception("Stack is empty")
value = self.stack[self.top]
self.top = (self.top - 1) % self.capacity
return value

def peek(self):
if self.is_empty():
raise Exception("Stack is empty")
return self.stack[self.top]

循环栈的实现与顺序栈的实现相似，只是在判断栈是否满和入栈、出栈时需要注意对数组下标的取模操作。