How to execute an action with st2client

from st2client.client import Client
from st2client.models.action import Execution

st2_client = Client(
    base_url='https://my-url/',
    auth_url='https://my-url/',
    api_url='https://my-url/api',
    api_key='XYZ'
)

execution = Execution()
execution.action = 'my_pack.my_action'
execution.parameters = {'domain': 'josetest1.co.za'}

execution_obj = st2_client.executions.create(execution)