使用pyvbox库创建虚拟机时出现TypeError

Question

我需要使用pyvbox创建虚拟机，以下代码出现此错误：

 File "..Python\lib\site-packages\virtualbox\library.py", line 8031, in create_machine

    raise TypeError("groups can only be an instance of type list")
TypeError: groups can only be an instance of type list 

#the code
import virtualbox


vbox = virtualbox.VirtualBox()

settings_file = "C:\VM"
name="vm_py"
os_type="Ubuntu_64"
flag=None
groups=None


vbox.create_machine(settings_file,name, groups,os_type,flag)