Detect the number of local variables declared in a function

Detect the number of local variables declared in a function.

def abc():
    x = 1
    y = 2
    S = "w3resource"
    print("Python Exercises")

# test
print(abc.__code__.co_nlocals)    # 3

See also

https://www.w3resource.com/python-exercises/python-functions-exercise-20.php