How can I get the named parameters from a URL using Flask?

When the user accesses this URL running on my flask app, I want the web service to be able to handle the parameters specified after the question mark:

http://10.1.1.1:5000/login?username=alex&password=pw1

#I just want to be able to manipulate the parameters
@app.route('/login', methods=['GET', 'POST'])
def login():
    username = request.form['username']
    print(username)
    password = request.form['password']
    print(password)