host key checking before running ansible playbook

testing_ansible.py

# ansible constants are set when module is imported
# set host key checking before ansible imports
import os
os.environ['ANSIBLE_HOST_KEY_CHECKING'] = 'false'
from ansible import utils
from ansible import callbacks
from ansible import inventory
import ansible.runner
import ansible.playbook
from ansible.callbacks import display

class runplaybook():

    def __init__(self):
        return

    @staticmethod
    def playbook(host, private_key_file, playbookfile):
        playbook_cb = callbacks.PlaybookCallbacks(verbose=utils.VERBOSITY)
        stats = callbacks.AggregateStats()
        runner_cb = callbacks.PlaybookRunnerCallbacks(stats, verbose=utils.VERBOSITY)
        inv = inventory.Inventory([host])

        playbook = ansible.playbook.PlayBook(
            remote_user="root",
            playbook=playbookfile,
            callbacks=playbook_cb,
            runner_callbacks=runner_cb,
            stats=stats,
            inventory=inv,
            private_key_file=private_key_file)
        results = playbook.run()

        return results