Check property Creates a function that will invoke a predicate function for the specified property on a given dictionary. Return a lambda function that takes a dictionary and applies the predicate function, fn to the specified property. def check_prop(fn, prop): return lambda obj: fn(obj[prop]) check_age = check_prop(lambda x: x >= 18, 'age') user = {'name': 'Mark', 'age': 18} check_age(user) # True