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Python - Stack Implementation using Array

Stack implementation using arrays in Python.
Run the code here: https://repl.it/@VinitKhandelwal/StckArray
from array import *

class Stack:

def __init__(self):
self.arr = array('i',[])

def peek(self):
if self.arr.__len__() > 0:
print(self.arr[-1])

def push(self, value):
self.arr.append(value)

def pop(self):
if self.arr.__len__() > 0:
self.arr.pop(-1)


class Node:

def __init__(self, value=None, pointer=None):
self.value = value
self.pointer = pointer


obj = Stack()
obj.peek()
obj.push(1)
obj.peek()
obj.push(2)
obj.peek()
obj.push(3)
obj.peek()
obj.pop()
obj.peek()
obj.pop()
obj.peek()
obj.pop()
obj.peek()
obj.pop()
obj.peek()

OUTPUT

1
2
3
2
1

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