def load_installed_version(self):
        installed_packages = get_installed_pypackages()
        if self.package in installed_packages:
            self.version = "=={}".format(
                installed_packages[self.package].version)
def memoized(*args):
        try:
            return stored_results[args]
        except KeyError:
            result = stored_results[args] = fn(*args)
            return result