Transaction Check types are not supported in get_checks

[rjelbert]

I have set up a Transaction Check on my Pingdom account which is running OK. I also have three Uptime checks configured. All four of these checks are tagged with "alarm". When I try and list the checks using theclient.get_checks(filters={"tags": ["alarm"]}) only the three Uptime checks are listed.
The Transaction Check does not seem to be included in the get_checks response.
I only want to check the status of this type of check and not create or modify it via the API.