Different outputs in Python2 and Python3

[MikeHill]

Hi All,
I am new to coding
When I run the following code in python2 and python3 I get different outputs
Can someone please explain this phenomenon

>>> a = [1,2,3,4,"hello"]
   >>> for i in a:
   ...     try:
   ...             print(i)
   ...             i+1
   ...             print (("i is : %d") %(i))
   ...     except:
   ...             print ("nope " + i + " is a string")


**Python 2 output**

   1
   2
   i is : 1
   2
   3
   i is : 2
   3
   4
   i is : 3
   4
   5
   i is : 4
   hello
   nope hello is a string

**Python 3 output**

   1
   i is :  1
   2
   i is :  2
   3
   i is :  3
   4
   i is :  4
   hello
   nope hello is a string