import sys
import clr
sys.path.append(r'C:\Users\Me\Projects\Dependencies\bin')
clr.AddReference('iCamstar')
from iCamstar import CamstarUtil
containers = []
camStar = CamstarUtil(host, port, username, password, workstation)
response = camStar.TestFunc(containers)
print(response)

...
Public Class CamstarUtil
  Public Structure MyContainer
    Dim ctnrName As String
    Dim productName As String
    Dim specName As String
    Dim description As String
    ...
  End Structure
  Public Sub New (ByVal host As String, ByVal port As String, ByVal user As String, ByVal pass As String, ByVal ws As String)
    ...
  End Sub
  Public Function TestFunc(ByVal containers As Collection(Of MyContainer))
    Return "Foo Bar"
  End Function
  ...

from System import Array
py_array = []
net_array = Array[int](py_array)
response = camStar.TestFunc(net_array)

clr.AddReference('System.Collections')
...
from System.Collections import *
...
containers = ArrayList()
...

from System.Collections.ObjectModel import Collection
...
containers = Collection[CamstarUtil.myContainer]()
...