Use GAE's Memcache to cache functions

gaecache.py

import google.appengine.api.memcache

DEFAULT_CACHE_TTL = 60 * 60 * 24

def cache(function, ttl=DEFAULT_CACHE_TTL):
    '''Cache `function` and its arguments for `ttl` seconds in GAE's
    Memcache.

    Usable as a decorator.
    '''
    def cache_function(*arguments, **keyword_arguments):
        function_name = '{}.{}'.format(function.__module__, function.__name__) 

        signature = (function_name, arguments, keyword_arguments)
        signature = str(signature)

        value = google.appengine.api.memcache.get(signature)

        if value is None:
            value = function(*arguments, **keyword_arguments)

            google.appengine.api.memcache.add(signature, value, time=ttl)

        return value

    return cache_function