Stack Program in Python

class Stack:
   def __init__(self):
      self.stack = []
   def add(self, data):
      if data not in self.stack:
         self.stack.append(data)
         return True
      else:
         return False

# Use peek to look at the top of the stack
   def peek(self):
      return self.stack[-1]

# Use list pop method to remove element
   def remove(self):
      if len(self.stack) <= 0:
         return ("No element in the Stack")
      else:
         return self.stack.pop()
stk = Stack()
stk.add(1)
stk.add(2)
stk.add(3)
stk.add(4)
stk.add(5)
print("topmost element: ",stk.peek())
print("----Deletion operation in stack----")
stk.remove()
stk.peek()
print("topmost element after deletion: ",stk.peek())