I want to verify that the objectID is a valid mongoID string.

Currently I have:

```
import bson
try:
  bson.objectid.ObjectId(id)
except:
  pass # do something

```

I wanted to make my exception more specific, and it looks like [there is a solution](http://api.mongodb.org/python/current/api/bson/errors.html), but `except bson.objectid.InvalidId` ends up in `TypeError: id must be an instance of (str, unicode, ObjectId)`.

Ok, I tried to look further and [found is\_valid method](http://api.mongodb.org/python/current/api/bson/objectid.html) but `bson.is_valid(1)` results in another error `TypeError: BSON data must be an instance of a subclass of str`.

So how can I properly check if my objectID is valid?