code: def render_css(self, fn=None, text=None, margin='', indent='\t'):
          
          fn = fn or os.path.splitext(self.fn)[0]+'.css'
          if not os.path.exists(os.path.dirname(fn)):
              os.makedirs(os.path.dirname(fn))
          curdir = os.path.abspath(os.curdir)
          os.chdir(os.path.dirname(fn))               # needed in order for scss to relative @import
          text = text or self.render_styles()
          if text != '': text = sass.compile(string=text)
          os.chdir(curdir)
          return CSS(fn=fn, text=text)
docs: output css using the Sass processor