mistake in when condition in config.yml file

TASK [ceilometer : Copying over existing policy.json] **************************
fatal: [localhost]: FAILED! => {"failed": true, "msg": "The conditional check 'ceilometer_policy.stat.exist' failed. The error was: error while evaluating conditional (ceilometer_policy.stat.exist): 'dict object' has no attribute 'exist'\n\nThe error appears to have been in '/home/vagrant/kolla/ansible/roles/ceilometer/tasks/config.yml': line 67, column 3, but may\nbe elsewhere in the file depending on the exact syntax problem.\n\nThe offending line appears to be:\n\n\n- name: Copying over existing policy.json\n ^ here\n"}

NO MORE HOSTS LEFT *************************************************************
 to retry, use: --limit @/home/vagrant/kolla/ansible/site.retry

PLAY RECAP *********************************************************************
localhost : ok=260 changed=163 unreachable=0 failed=1

Command failed ansible-playbook -i ansible/inventory/all-in-one -e @/etc/kolla/globals.yml -e @/etc/kolla/passwords.yml -e CONFIG_DIR=/etc/kolla -e action=deploy /home/vagrant/kolla/ansible/site.yml