pattern = r"(your base)"
sentence = "All your base are belong to us."

match = re.search(pattern, sentence)
match.group(1)
# Out: 'your base'

match = re.search(r"(belong.*)", sentence)
match.group(1)
# Out: 'belong to us.'

Searching is done anywhere in the string unlike re.match. You can also use re.findall.

You can also search at the beginning of the string (use ^),

match = re.search(r"^123", "123zzb")
match.group(0)
# Out: '123'

match = re.search(r"^123", "a123zzb")
match is None
# Out: True

at the end of the string (use $),

match = re.search(r"123$", "zzb123")
match.group(0)
# Out: '123'

match = re.search(r"123$", "123zzb")
match is None
# Out: True

or both (use both ^ and $):

match = re.search(r"^123$", "123")
match.group(0)
# Out: '123'