Place items with deterministic z ordering

[MasterOdin]

Sample script:

import time
from pagi_api import connectSocket, Agent
cs = connectSocket()
print("destroy items")
agent = Agent(cs)
agent.createItem('/Users/mpeveler/Github/pyPAGI/grid.png', 50, -10.5, -1, 'grid3', 1, 0, 0, 0)
time.sleep(2)
agent.createItem('/Users/mpeveler/Github/pyPAGI/fridge-small.jpg', 50, -9.3, 1.5, 'fridge', 1, 0, 0, 1)
time.sleep(2)
agent.createItem('/Users/mpeveler/Github/pyPAGI/soda-small.png', 50, -8.8, 8.4, 'soda', 1, 0, 0, 1)
cs.close()

I would expect that grid is placed first, then the fridge, and the soda such that all three are visible with the fridge and soda placed on/overlaying the grid. However, often, the grid will overlap one or both of the created custom items. Changing the ordering of these commands does not give me a deterministic way to place images how I'd want and always the grid is on top of one of the other two images.