import re
import time

s = 'HAPPY'
rx = re.compile(r'(?=(..))', re.DOTALL)

def test_regex():
	return rx.findall(s)

def test_comprehension():
	return [(s)[i:i+2] for i in range(0,len(s)-1)]

n = 10000
t0 = time.time()
for i in range(n): test_regex()
t1 = time.time()

print('regex: {}'.format(t1-t0))

t0 = time.time()
for i in range(n): test_comprehension()
t1 = time.time()

print('comprehension: {}'.format(t1-t0))