old_contents: class Stack:
  
      def __init__(self):
          self.stack = []
  
      def push(self, data):
          self.stack.append(data)
  
      def pop(self):
          self.stack.pop()
  
      def isEmpty(self):
          if self.stack == []:
              print("True")
          else:
              print("False")
  
      def size(self):
          print(len(self.stack))
  
      def viewTop(self):
          if self.stack != []:
              print(self.stack[len(self.stack) - 1])
          else:
              print("There are no elements in the stack")
  
      def viewFullStack(self):
          for i in self.stack:
              print(i)
new_contents: class Stack:
  
      # constructor
      # here we initialize the list that will be used for the stack
      def __init__(self):
          self.stack = []
  
      # method to push element into the stack
      def push(self, data):
          self.stack.append(data)
  
      # method to pop topmost i.e. last element from the stack
      def pop(self):
          self.stack.pop()
  
      # method to find whether the stack is empty or not
      def isEmpty(self):
          if not self.stack:
              print("True")
          else:
              print("False")
  
      # method to find the current length of the stack
      def size(self):
          print(len(self.stack))
  
      # method to view the top most element
      def viewTop(self):
          if self.stack:
              print(self.stack[len(self.stack) - 1])
          else:
              print("There are no elements in the stack")
  
      # method to view the full stack
      def viewFullStack(self):
          for i in self.stack:
              print(i)
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