The first thing you need to get is a list of the Dedicated Hosts on your account. To list the Dedicated Hosts on your account you can use the following code:
import SoftLayer
from pprint import pprint as pp
client = SoftLayer.Client()
dedicatedHosts = client['SoftLayer_Account'].getDedicatedHosts()
pp(dedicatedHosts)
Once you have the Dedicated Host ID you can use the following code to retrieve the Virtual Guests on the host.
"""
@service SoftLayer_Virtual_DedicatedHost
@author Ryan TIffany
"""
import SoftLayer
from pprint import pprint as pp
dhId = 10001
client = SoftLayer.Client()
getGuests = client['SoftLayer_Virtual_DedicatedHost'].getGuests(id=dhId)
pp(getGuests)