Apparently you looked at the doc from mongo, you should look at the doc from pymongo http://api.mongodb.org/python/current/api/pymongo/database.html
From that, the correct command should be:
db.command("cloneCollection", collection="databaseName.dump", from="example.com:6001")
Edit
Since from
is a python keyword, we probably need to create a dict and unpack it:
db.command("cloneCollection", **{'collection': "databaseName.dump", 'from': "example.com:6001"})