area of a circle in python

#Area Of A Circle in python
R = int(input("Enter the radius of the circle: "))
PI = 22/7 #This is a constant
A = PI * R * R

Here is what the above code is Doing:
1. We are taking the radius of the circle as an input from the user.
2. We are storing the value of PI in a variable.
3. We are calculating the area of the circle using the formula.
4. We are printing the area of the circle.