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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 browser_cache(seconds):
 """Decorator for browser cache. Only for webpy @browser_cache( seconds ) before GET/POST function. """

    import web
    def wrap(f):
        def wrapped_f(*args):
            last_time_str = web.ctx.env.get('HTTP_IF_MODIFIED_SINCE', '')
            last_time = web.net.parsehttpdate(last_time_str)
            now = datetime.datetime.now()
            if last_time and\
                    last_time + datetime.timedelta(seconds = seconds) > now:
                web.notmodified()
            else:
                web.lastmodified(now)
                web.header('Cache-Control', 'max-age='+str(seconds))
            yield f(*args)
        return wrapped_f
    return wrap