Whitespace on both sides:

s = "  \t a string example\t  "
s = s.strip()

Whitespace on the right side:

s = s.rstrip()

Whitespace on the left side:

s = s.lstrip()

As thedz points out, you can provide an argument to strip arbitrary characters to any of these functions like this:

s = s.strip(' \t\n\r')

This will strip any space, \t, \n, or \r characters from the left-hand side, right-hand side, or both sides of the string.

The examples above only remove strings from the left-hand and right-hand sides of strings. If you want to also remove characters from the middle of a string, try re.sub:

import re
print re.sub('[\s+]', '', s)

That should print out: