import multiprocessing
from itertools import islice
def split(infilename, num_cpus=multiprocessing.cpu_count()):
    with open(infilename) as f:
        count = sum(1 for _ in f)
        f.seek(0)
        lines = [list(islice(f, count // num_cpus)) for _ in range(num_cpus)]
        lines[-1] += islice(f, None)
        return lines

files = split("sample_simple.csv")
print(len(files))
for ifile in files:
    reader = csv.reader(ifile)
    for row in reader:
        print len(row)