Python Programming

Now we are ready to talk about decorators.

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def christmas_decorator(func):
    def wrapper():
        print("wrapping")
        func()
        print("with a Christmas-y wrapper")
    return wrapper

def gift():
    print("a toy")

print("Before decorating:")
gift()
print(gift) # <function gift at 0x7f12ffd0c1f0>

print("After decorating:")
gift = christmas_decorator(gift)
gift()
print(gift) # <function christmas_decorator.<locals>.wrapper at 0x7f12ffd0c280>

Above is an example of a Python decorator.

• A Python decorator is a function (Line 1).
• It takes another function as input (Line 1).
• It wraps this function and adds more functionality to the function (yes, try saying three functions in one sentence!) (Lines 3-5)
• It returns the function (Line 6)
• It reassigns the returned function to the name of the original function (Line 16)

Hopefully it all makes sense!