Python Tools

batch.py

from itertools import islice, chain


def batch(iterable, size):
    iterator = iter(iterable)
    for first in iterator:
        yield chain([first], islice(iterator, size - 1))

cache.py

import os
import pickle


def cache(function):
    def wrapper(*args, **kwargs):
        key = '.cache/%s-%s' % (function.__name__, ','.join(args))
        if os.path.exists(key):
            with open(key, 'rb') as f:
                return pickle.load(f)
        result = function(*args, **kwargs)
        path, filename = os.path.split(key)
        os.makedirs(path, exist_ok=True)
        with open(key, 'wb') as f:
            pickle.dump(result, f)
        return result
    return wrapper

  
@cache
def expensive_call():
  """Some expensive function call"""
  pass