Might be nicer to separate out the string formatting, though, so that there isn't too much logic on one line:
```python
body_tpl_path = "emails/{base}_body.txt".format(base=message_base)
message = edxmako.lookup['main'].get_template(body_tpl_path).render()
subject_tpl_path = "emails/{base}_subject.txt".format(base=message_base)
subject = edxmako.lookup['main'].get_template(subject_tpl_path).render().strip()
```