re.sub example
Example 1: python re compile
import re
# Compile a regular expression pattern into a regular expression object, which can be used for matching using its match(), search() and other methods, described below.
prog = re.compile(pattern)
result = prog.match(string)
# is equivalent to
result = re.match(pattern, string)
Example 2: re.sub in python example
import re
result = re.sub(pattern, repl, string, count=0, flags=0);
Example 3: validate string using six library python
from six import string_types
isinstance(s, string_types)