The answer that I found on the web is to use request.args.get. However, I cannot manage it to work. I have the following simple example:

from flask import Flask
app = Flask(__name__)

@app.route("/hello")
def hello():
    print request.args['x']
    return "Hello World!"

if __name__ == "__main__":
    app.run()

I go to the 127.0.0.1:5000/hello?x=2 in my browser and as a result I get:

Internal Server Error

The server encountered an internal error and was unable to complete your request. Either the server is overloaded or there is an error in the application.

What am I doing wrong?