Project items are removed from the url when calling TFSAPI

I am specifying a Collection as well as a Project in the call to TFSAPI, however when I try to retrieve a work item there is a HTTPError: 401 Client Error: Unauthorized for url...However, I noticed that the project has been removed from the url and this could be causing the authentication error.
call to TFSAPI:
>>client = TFSAPI("https://tfsserver:8080/tfs/", project="CollectionName/ProjectName", user=user, password=password, auth_type=HttpNtlmAuth)
>>workitem = client.get_workitem(10)
Error:
...requests.exceptions.HTTPError: 401 Client Error: Unauthorized for url: https://tfsserver:8080/tfs/CollectionName/_apis/wit/workitems?ids=10&$expand=all&api-version=1.0