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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 show_key(self, value):
 """ Get a specific canned key :type value: str :param value: Canned key to show :rtype: dict :return: A dictionnary containing canned key description """

        keys = self.get_keys()
        keys = [x for x in keys if x['label'] == value]
        if len(keys) == 0:
            raise Exception("Unknown key")
        else:
            return keys[0]