code: def minify(self, css):
        
        css = css.replace("\r\n", "\n") # get rid of Windows line endings, if they exist
        for rule in _REPLACERS[self.level]:
            css = re.compile(rule[0], re.MULTILINE|re.UNICODE|re.DOTALL).sub(rule[1], css)
        return css
docs: Tries to minimize the length of CSS code passed as parameter. Returns string.