Python 获取名称错误：未定义名称“IMGS”，虽然我已在类中定义了它

在bird类中，定义了变量IMGS，但是如果将其声明为全局变量，则会出现名称错误

**BIRD_IMGS** = [pygame.transform.scale2x(pygame.image.load(os.path.join("imgs", "bird1.png"))), pygame.transform.scale2x(pygame.image.load(os.path.join("imgs", "bird2.png"))), pygame.transform.scale2x(pygame.image.load(os.path.join("imgs", "bird3.png")))]

class Bird:
    **IMGS** = BIRD_IMGS
    MAX_ROTATION = 25
    ROT_VEL = 20
    ANIMATION_TIME = 5

    def __init__(self, x, y):
        self.x = x
        self.y = y
        self.tilt = 0
        self.tick_count = 0
        self.vel = 0
        self.height = self.y
        self.img_count = 0
        self.img = self.IMGS[0]

    def draw (self, win):
        self.img_count += 1

NameError:未定义名称“IMGS”

    # to make the wing flapping animation
        if self.img_count < self.ANIMATION_TIME:
            self.img = IMGS[0]
        elif self.img_count < self.ANIMATION_TIME*2:
            self.img = IMGS[1]
        elif self.img_count < self.ANIMATION_TIME*3:
            self.img = IMGS[2]
        elif self.img_count < self.ANIMATION_TIME*4:
            self.img = IMGS[1]
        elif self.img_count < self.ANIMATION_TIME*4 + 1:
            self.img = IMGS[0]

---

在类块顶层定义的主

名称将成为类对象的类属性，由类的所有实例共享-它们不会在全局模块命名空间中公开。注意，您必须通过类或其实例来访问它们，即：

print(Bird.IMGS)
b = Bird()
print(b.IMGS)
print(b.IMGS is Bird.IMGS)

由于Python没有隐式this指针，因此在方法中，必须使用当前实例self来访问该属性：

if self.img_count < self.ANIMATION_TIME:
    self.img = self.IMGS[0]