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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 as_cql_query(self):
 """ Returns a CQL query string that can be used to recreate just this keyspace, not including user-defined types and tables. """

        if self.virtual:
            return "// VIRTUAL KEYSPACE {}".format(protect_name(self.name))
        ret = "CREATE KEYSPACE %s WITH replication = %s " % (
            protect_name(self.name),
            self.replication_strategy.export_for_schema())
        return ret + (' AND durable_writes = %s' % ("true" if self.durable_writes else "false"))