The documented way to execute module code locally wasn't always working:
$ python ./lib/ansible/modules/files/file.py <<< '{"ANSIBLE_MODULE_ARGS": {}}'
Traceback (most recent call last):
File "./lib/ansible/modules/files/file.py", line 177, in <module>
from ansible.module_utils.basic import AnsibleModule
File "~/ansible/lib/ansible/module_utils/basic.py", line 78, in <module>
import tempfile
File "~/ansible/lib/ansible/modules/files/tempfile.py", line 69, in <module>
from tempfile import mkstemp, mkdtemp
ImportError: cannot import name 'mkstemp'