from thrift.transport import TSSLSocket
from thrift.transport import TTransport
import cql

sock = TSSLSocket.TSSLSocket(host='cass.example.com', port=9160, ca_certs='/path/to/ca_certs.pem')
trans = TTransport.TFramedTransport(sock)

conn = cql.connect('cass.example.com', 9160, 'keyspace', user='username', password='password', transport=trans, cql_version='3.0.0')