Defining Virtual Server 'Type' in iControlREST API

So I'm struggling to find how to define a virtual-server type (i.e. Standard, Forwarding, Performance, etc.) when creating a virtual-server in the REST API. I'm using the python SDK and I can successfully create a virtual-server using this methodology:

    mgmt = ManagementRoot(big_ip, big_ip_user, big_ip_pass)
    ltm = self.mgmt.tm.ltm
    ltm.virtuals.virtual.create(name=name, destination='192.168.10.1:80', mask='255.255.255.255')

This works fine but it is created as a Performance L4 virtual-server. I don't see any deterministic properties to implicitly say what the VS type is when creating, or modifying a VS.

Am I missing something, or is the VS type defined by the policies/properties that you allocate to it? I.e. if I add an iRule with HTTP inspection, does the VS type automatically become Standard?