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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 list_user_access(self, user):
 """ Returns a list of all database names for which the specified user has access rights. """

        user = utils.get_name(user)
        uri = "/%s/%s/databases" % (self.uri_base, user)
        try:
            resp, resp_body = self.api.method_get(uri)
        except exc.NotFound as e:
            raise exc.NoSuchDatabaseUser("User '%s' does not exist." % user)
        dbs = resp_body.get("databases", {})
        return [CloudDatabaseDatabase(self, db) for db in dbs]