tiwijo

from functools import wraps
import inspect

def first(fn):
    '''Wrap a function so True is returned the first time it is called.'''

    @wraps(fn)
    def wrapper(self, *args, **kwargs):
        if self.first:
            self.first = False

tiwijo

from itertools import tee, izip

def inwise(iterable, n=2):
    '''Return an iterator over iterable where n adjacent items are returned at
       a time.

       @param n : int
           the number of adjacent items to return'''

    iters = tee(iterable, n=n)

tiwijo

#! /usr/bin/env python

from itertools import izip_longest

def ichunk(iterable, n):
    '''Chunk n adjacent elements in the iterable. For example
       ichunk((1,2,3,4,5,6), 2) -> (1,2),(3,4),(5,6)'''

    iters = (iter(iterable),) * n
    return izip_longest(*iters, fillvalue=None)