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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 get_compute(self, compute_id):
 """ Returns a compute server or raise a 404 error. """

        try:
            return self._computes[compute_id]
        except KeyError:
            if compute_id == "vm":
                raise aiohttp.web.HTTPNotFound(text="You try to use a node on the GNS3 VM server but the GNS3 VM is not configured")
            raise aiohttp.web.HTTPNotFound(text="Compute ID {} doesn't exist".format(compute_id))