Better would be to add a doc string that explains this functions purpose. Like:

```python
def include_symbol(tablename, schema):
    """Return true so this table is included, if NOT...
        * not in default or bixie schema
        * any partitioned tables (ending in '_20130601' for example)
    """"
    return schema in (None, "bixie") and re.search(r'_\d{8}$', tablename) is None
```