Python/Regex

To Match

import re

sample1 = "2018-05-31"
sample2 = "Today is 2018-51-31."
pattern = "\d{4}-\d{2}-\d{2}"

m = re.search(pattern, sample1)
if m:
    print('Found pattern in sample1.')

m = re.search(pattern, sample2)
if m:
    print('Found pattern in sample2.')

m = re.match(pattern, sample1)
if m:
    print('Match pattern sample1.')

m = re.match(pattern, sample2)
if m:
    print('Match pattern sample2.')

To Replace

ns = re.sub('o+', '_', 'doooooog')