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Solve the following problem using Python, implementing the functions described below, one line at a time
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<USER_TASK:>
Description:
 def create_router(self, context, router):
 """Create a new router entry in DB, and create it Arista HW."""


        # Add router to the DB
        new_router = super(AristaL3ServicePlugin, self).create_router(
            context,
            router)
        # create router on the Arista Hw
        try:
            self.driver.create_router(context, new_router)
            return new_router
        except Exception:
            with excutils.save_and_reraise_exception():
                LOG.error(_LE("Error creating router on Arista HW router=%s "),
                          new_router)
                super(AristaL3ServicePlugin, self).delete_router(
                    context,
                    new_router['id']
                )