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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 parse_option(self, option, block_name, message):
 """ Parse show, end_show, and timer_show options. """


        if option == 'show':
            option = 'start_' + option

        key = option.split('_', 1)[0]
        self.messages[key] = message