'`query_string` should be a literal CQL statement with the exception
of parameter placeholders that will be filled through the
`parameters` argument of :meth:`.Session.execute()`.
See :class:`Statement` attributes for a description of the other parameters.'

def __init__(self, query_string, retry_policy=None, consistency_level=None, routing_key=None, serial_consistency_level=None, fetch_size=FETCH_SIZE_UNSET, keyspace=None, custom_payload=None, is_idempotent=False):

    Statement.__init__(self, retry_policy, consistency_level, routing_key, serial_consistency_level, fetch_size, keyspace, custom_payload, is_idempotent)
    self._query_string = query_string
