Nonlocal keyword in Python - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to modify the outer variable inside the inner function using the nonlocal keyword.

Python

def outer():
    count = 0
    def inner():
        [1] count
        count += 1
        return count
    return inner()

result = outer()

Drag options to blanks, or click blank then click option'

Adef

Bglobal

Cnonlocal

Dlocal

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'global' instead of 'nonlocal' causes an error because 'count' is not global.

Forgetting to declare 'nonlocal' means the inner function creates a new local variable.

The 'nonlocal' keyword allows the inner function to modify the variable 'count' defined in the outer function.

2fill in blank

medium

Complete the code to correctly increment the outer variable using the nonlocal keyword.

Python

def counter():
    num = 10
    def increment():
        [1] num
        num += 5
        return num
    return increment()

result = counter()

Drag options to blanks, or click blank then click option'

Adef

Bglobal

Clocal

Dnonlocal

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'global' causes an error because 'num' is not a global variable.

Not declaring 'nonlocal' causes 'num' to be treated as local, leading to an UnboundLocalError.

Using 'nonlocal' allows the inner function to modify 'num' from the outer function.

3fill in blank

hard

Fix the error by adding the correct keyword to modify the outer variable inside the nested function.

Python

def make_multiplier():
    factor = 3
    def multiply(x):
        [1] factor
        factor += 1
        return x * factor
    return multiply

mult = make_multiplier()
result = mult(5)

Drag options to blanks, or click blank then click option'

Aglobal

Bnonlocal

Clocal

Ddef

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'global' causes an error because 'factor' is not global.

Omitting 'nonlocal' causes a local variable error.

The 'nonlocal' keyword is needed to access and modify 'factor' from the outer function inside 'multiply'.

4fill in blank

hard

Fill both blanks to correctly update the outer variable and return its new value.

Python

def accumulator():
    total = 0
    def add(value):
        [1] total
        total [2] value
        return total
    return add

acc = accumulator()
result = acc(7)

Drag options to blanks, or click blank then click option'

Anonlocal

B+=

C-=

Dglobal

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'global' instead of 'nonlocal' causes errors.

Using '-=' instead of '+=' changes the logic incorrectly.

Use 'nonlocal' to modify 'total' from the outer function and '+=' to add the value.

5fill in blank

hard

Fill all three blanks to create a nested function that modifies and returns the outer variable correctly.

Python

def counter(start):
    count = start
    def increment():
        [1] count
        count [2] 1
        return [3]
    return increment

inc = counter(100)
result = inc()

Drag options to blanks, or click blank then click option'

Anonlocal

B+=

Ccount

Dglobal

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'global' instead of 'nonlocal' causes errors.

Returning a wrong variable or value.

Forgetting to declare 'nonlocal' causes UnboundLocalError.

Declare 'count' as nonlocal, increment it with '+=', and return the updated 'count'.