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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 opt_display(self, display):
 """ Set value for display option """

        key = get_enum_key(display, DISPLAYS)
        if key is not None:
            self.conf["display"] = key
            self.display = DISPLAYS[key]
            print("Set display %r" % key)
        else:
            print("Unknown display %r" % display)