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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 accept(self, value):
 """ Add an Accept option to a request. :param value: the Accept value """

        if value in list(defines.Content_types.values()):
            option = Option()
            option.number = defines.OptionRegistry.ACCEPT.number
            option.value = value
            self.add_option(option)