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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 get(self, key):
 """ Get parsed result. After :func:`parse` the argv, we can get the parsed results:: # command.option('-f', 'description of -f') command.get('-f') command.get('verbose') # we can also get ``verbose``: command.verbose """


        value = self._results.get(key)
        if value is not None:
            return value

        # get from option default value
        option = list(filter(lambda o: o.key == key, self._option_list))
        if not option:
            raise ValueError('No such option: %s' % key)

        option = option[0]
        return option.default