python code writing practice

Sure, here's a simple code to calculate the factorial of a number using recursion in Python:

def factorial(num):
    if num == 0:
        return 1
    else:
        return num * factorial(num-1)

# Test the function
num = 5
print("Factorial of", num, "is", factorial(num))

In this code, we define a function `factorial` that takes a number as input and returns its factorial. We use recursion to calculate the factorial - if the number is 0, we return 1 (since 0! = 1), otherwise we call the `factorial` function recursively for `num-1` and multiply the result with `num`.

We then test the function by calling it with the number 5 and printing the result. You can try running this code and testing the function with different inputs.