Pickle Expensive Computations

load_or_compute.py

import cPickle as pickle
import bz2

def load_or_compute(method, filename, recompute=False):

    try:
        if recompute: raise Exception
        fp = bz2.BZ2File(filename)
        return pickle.load(fp)
        fp.close()

    except:
        if recompute is True:
            print "Recompute is True! Recomputing all data in file %s." % filename
        else:
            print "Error reading file: %s. Recomputing all data."  % filename

        fp = bz2.BZ2File(filename, "w")
        item = method()
        pickle.dump(item, fp, pickle.HIGHEST_PROTOCOL)
        fp.close()
        return item