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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 handle(self, *args, **options):
 """ Forward to the right sub-handler """

        if options["sub_command"] == "add":
            self.handle_add(options)
        elif options["sub_command"] == "update":
            self.handle_update(options)
        elif options["sub_command"] == "details":
            self.handle_details(options["username"])
        elif options["sub_command"] == "list":
            self.handle_list(options["all"], options["csv"])