Interleave two or more lists

list_interleave_benchmark.py

from itertools import chain
import perfplot

def cs1(l):
    def _cs1(l):
        for i, x in enumerate(l, 1):
            yield x
            yield f'{x}_{i}'

    return list(_cs1(l))

def cs2(l):
    out_l = [None] * (len(l) * 2)
    out_l[::2] = l
    out_l[1::2] = [f'{x}_{i}' for i, x in enumerate(l, 1)]

    return out_l

def cs3(l):
    return list(chain.from_iterable(
        zip(l, [f'{x}_{i}' for i, x in enumerate(l, 1)])))
  
def ajax(l):
    return [
        i for b in [[a, '{}_{}'.format(a, i)] 
        for i, a in enumerate(l, start=1)] 
        for i in b
    ]
  
def ajax_cs0(l):
    # suggested improvement to ajax solution
    return [j for i, a in enumerate(l, 1) for j in [a, '{}_{}'.format(a, i)]]

def chrisz(l):
    return [
        val 
        for pair in zip(l, [f'{k}_{j+1}' for j, k in enumerate(l)]) 
        for val in pair
    ]
  
  
kernels = [cs1, cs2, cs3, ajax_cs0, ajax, chrisz]

perfplot.show(
    setup=lambda c: list('abcd') * c,
    kernels=kernels,
    labels=[f.__name__ for f in kernels],
    n_range=[2**k for k in range(0, 15)],
    xlabel='N',
    equality_check=lambda x, y: x == y)