What is the difference between, a + 1 and a += 1 and a = a + 1?

Q. What is the difference between, a + 1 and a += 1 and a = a + 1? To find out, execute the following code fragments and write your answer below:

Fragment 1

a = 20

a + 1

print (a)

Fragment 2

a = 20

a += 1

print (a)

Fragment 3

a = 20

a = a + 1

print ()

Answer :-

Output fragment 1:- 21

But value of variable ‘a’ will not change.

Output fragment 2: -21

But value of variable ‘a’ will change. Now new value of variable ‘a’ is 21.

Output fragment 3: -It will print nothing because print statement is empty.

But value of variable ‘a’ will change. Now new value of variable ‘a’ is 21.