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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def render_css(self, fn=None, text=None, margin='', indent='\t'):
 """output css using the Sass processor"""

        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)