如何修复 Ursina 引擎中的 "name 'render' is not defined"?

How to fix "name 'render' is not defined" in Ursina Engine?

所以我刚刚开始使用“Ursina”引擎,我对它还是很陌生。我正在尝试使用此引擎在 Youtube 教程上制作 Minecraft 游戏。出于某种原因,该程序一直给我错误名称“名称 'render' 未定义”。我不明白那是什么意思。我试图修复我的代码并浏览了代码但找不到答案。

这是我的全部代码:

from ursina import *
from ursina.prefabs.first_person_controller import FirstPersonController

Sky(texture = 'sky.jpg')

class Voxel(Button):
    def __init__(self, position = (0,0,0)):
        super().__init__(
            model = 'cube',
            texture = 'white_cube',
            position = position,
            color = color.white,
            parent = scene,
            origin_y = 0.5,
            highlight_color = color.lime,
        )
    
app = Ursina()
player = FirstPersonController()
for x in range(12):
    for y in range(12):
        voxel = Voxel(position = (y,0,x))


app.run() 

这是代码的回溯:

PS C:\Users\lhnguyen1029> & "C:/Program Files (x86)/Python39- 
32/python.exe" "c:/Users/lhnguyen1029/OneDrive - Mesa Public 
Schools/Documents/CTE- Computer Science Principles/Ursina 
practice/ursina_practice(2).py"
package_folder: 
C:\Users\lhnguyen1029\AppData\Roaming\Python\Python39\site- 
packages\ursina
asset_folder: c:\Users\lhnguyen1029\OneDrive - Mesa Public 
Schools\Documents\CTE- Computer Science Principles\Ursina practice
screen resolution: (1366, 768)
Traceback (most recent call last):
 File "c:\Users\lhnguyen1029\OneDrive - Mesa Public 
Schools\Documents\CTE- Computer Science Principles\Ursina 
practice\ursina_practice(2).py", line 7, in <module>
Sky(texture = 'sky.jpg')
File "C:\Users\lhnguyen1029\AppData\Roaming\Python\Python39\site- 
packages\ursina\prefabs\sky.py", line 8, in __init__
parent = render,
NameError: name 'render' is not defined
PS C:\Users\lhnguyen1029> 

在实例化实体之前实例化 Ursina()。