Why patterns improve code quality in Flask - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a Flask app instance.

Flask

from flask import Flask
app = Flask([1])

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

A__name__

BNone

CFlask

Dapp

Attempts:

3 left

💡 Hint

Common Mistakes

Using the app variable name instead of __name__

Passing the class Flask instead of a string

Passing None which causes errors

The Flask app instance requires the current module name, which is given by __name__.

2fill in blank

medium

Complete the code to define a route that returns 'Hello World!'.

Flask

@app.route([1])
def hello():
    return 'Hello World!'

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

A'/home'

B'/hello'

C'/'

D'/index'

Attempts:

3 left

💡 Hint

Common Mistakes

Using a route other than '/' for the home page

Forgetting to put quotes around the route string

The root URL '/' is the common pattern for the home page route.

3fill in blank

hard

Fix the error in the code to run the Flask app only when the script is executed directly.

Flask

if [1] == '__main__':
    app.run(debug=True)

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

A__name__

Bapp.name

Cmain

Dapp.__name__

Attempts:

3 left

💡 Hint

Common Mistakes

Using app.name instead of __name__

Comparing to 'main' without underscores

Using app.__name__ which is incorrect

The special variable __name__ equals '__main__' when the script runs directly.

4fill in blank

hard

Fill both blanks to create a route that accepts a username parameter and returns a greeting.

Flask

@app.route('/user/<[1]>')
def greet([2]):
    return f'Hello, {{ [2] }}!'

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

Ausername

Bname

Cuser

Did

Attempts:

3 left

💡 Hint

Common Mistakes

Using different names in the route and function parameter

Using generic names like 'id' that don't match the route

The route parameter and function argument must match to pass the username correctly.

5fill in blank

hard

Fill all three blanks to create a dictionary comprehension that maps route names to their functions if the function name starts with 'view_'.

Flask

routes = { [1]: [2] for [3] in dir(app) if [1].startswith('view_') }

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

Afunc_name

Bgetattr(app, func_name)

Dname

Attempts:

3 left

💡 Hint

Common Mistakes

Using different variable names inconsistently

Not using getattr to access the function

Filtering on the wrong variable

The comprehension iterates over function names, uses getattr to get the function, and filters by name prefix.