cql error

[A J]

cqlsh> CREATE KEYSPACE twissandra with
   ...   strategy_class =
   ...     'org.apache.cassandra.locator.NetworkTopologyStrategy'
   ...   and strategy_options=[{DC1:1,  DC2:1}];
Bad Request: line 4:37 no viable alternative at character ']'


What is wrong with the above syntax ?

Thanks.