Solution decorators decorator

---

examples/decorators/fibonacci.py

import sys
import memoize_attribute
import memoize_nonlocal
import decor_any

#@memoize_attribute.memoize
#@memoize_nonlocal.memoize
#@decor_any.tron
def fibonacci(n):
    if n == 1:
        return 1
    if n == 2:
        return 1
    return fibonacci(n-1) + fibonacci(n-2)

if __name__ == '__main__':
    if len(sys.argv) != 2:
        sys.stderr.write("Usage: {} N\n".format(sys.argv[0]))
        exit(1)
    print(fibonacci(int(sys.argv[1])))

examples/decorators/memoize_nonlocal.py

def memoize(f):
    data = {}
    def caching(n):
        nonlocal data
        key = n
        if key not in data:
            data[key] = f(n)
        return data[key]

    return caching

examples/decorators/memoize_attribute.py

def memoize(f):
    def caching(n):
        key = n
        #if 'data' not in caching.__dict__:
        #    caching.data = {}
        if key not in caching.data:
            caching.data[key] = f(n)
        return caching.data[key]
    caching.data = {}

    return caching

Before

$ time python fibonacci.py 35
9227465

real   0m3.850s
user   0m3.832s
sys    0m0.015s

After

$ time python fibonacci.py 35
9227465

real   0m0.034s
user   0m0.019s
sys    0m0.014s