The get() method on dicts and its "default" argument

name_for_userid = {
    382: "Alice",
    590: "Bob",
    951: "Dilbert",
}


def greeting(userid):
    return "Hi %s!" % name_for_userid.get(userid, "there")


r = greeting(382)
# r: "Hi Alice!"

r = greeting(333333)
# r: "Hi there!"

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