capture essence regex mislay them, efficiently

situation:

• text: string


• r: regex matches biased string. competence costly calculate.

i wish both mislay r-matches text, indeed contain. currently, i like:

import re
ab_re = re.compile("[ab]")
text="abcdedfe falijbijie bbbb laifsjelifjl"
ab_re.findall(text)
# ['a', 'b', 'a', 'b', 'b', 'b', 'b', 'b', 'a']
ab_re.sub('',text)
# 'cdedfe flijijie  lifsjelifjl'

this runs regex twice, circuitously i tell. there technique pass, maybe controlling re.split? seems separate formed solutions i'd need regex during slightest twice well.