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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 gen_static(self, output_folder):
 """ Generates a complete static version of the web site. It will stored in output_folder. """

        files = []
        for l in self.file_listers:
            files += l()
        for f in files:
            _logger.info("generating %s" % f)
            content = self.get(f)
            loc = os.path.join(output_folder, f)
            d = os.path.dirname(loc)
            if not os.path.exists(d):
                os.makedirs(d)
            with open(loc, "wb") as file_:
                file_.write(content)