input: Write a python function to implement a stack that can handle a maximum of 10 elements.
  assert stack.push(1) is None
  assert stack.push(2) is None
  assert stack.push(3) is None
  assert stack.push(4) is None
  assert stack.push(5) is None
  assert stack.pop() == 5
  assert stack.pop() == 4
  assert stack.pop() == 3
output: class Stack:
      def __init__(self):
          self.stack = []
          self.max_size = 10
  
      def push(self, value):
          if len(self.stack) < self.max_size:
              self.stack.append(value)
          else:
              raise IndexError("Stack overflow")
  
      def pop(self):
          if self.stack:
              return self.stack.pop()
          else:
              raise IndexError("Stack underflow")
  
  stack = Stack()