import re
# d is equivalent to [0-9].
p = re.compile('d')
print(p.findall("I went to him at 9 A.M. on 5th March 1999"))
# d+ will match a group on [0-9], group
# of one or greater size
p = re.compile('d+')
print(p.findall("I went to him at 9 A.M. on 5th July 1999"))