contrail generate python source from instance_service.thrift

1)
$sudo apt-get install thrift-compiler

2)
$git clone https://github.com/Juniper/contrail-controller
$cd contrail-controller/src/vnsw/agent/openstack

3)
contrail-controller/src/vnsw/agent/openstack$ ls
instance_service_server.cc  instance_service_server.h  instance_service.thrift  SConscript  test

4)
contrail-controller/src/vnsw/agent/openstack$ thrift --gen py instance_service.thrift

5)
contrail-controller/src/vnsw/agent/openstack$ ls
gen-py  instance_service_server.cc  instance_service_server.h  instance_service.thrift  SConscript  test

6)
contrail-controller/src/vnsw/agent/openstack$ ls gen-py/
__init__.py  instance_service

7)
contrail-controller/src/vnsw/agent/openstack$ ls gen-py/instance_service/
constants.py  __init__.py  InstanceService.py  InstanceService-remote  ttypes.py