diff --git a/bullet.py b/bullet.py
deleted file mode 100644
index 1bd37b6..0000000
--- a/bullet.py
+++ /dev/null
@@ -1,33 +0,0 @@
-import pygame
-from pygame.sprite import Sprite
-
-class Bullet(Sprite):
-    """一个对飞船发射的子弹进行管理的类"""
-
-    def __init__(self, ai_settings, screen, ship):
-        """在飞船所处的位置创建一个子弹对象"""
-        super().__init__()
-        self.screen = screen
-
-        # 在(0,0)处创建一个表示子弹的矩形，再设置正确的位置
-        self.rect = pygame.Rect(0, 0, ai_settings.bullet_width, ai_settings.bullet_height)
-        self.rect.centerx = ship.rect.centerx
-        self.rect.bottom = ship.rect.top
-
-        # 存储用小数表示的子弹位置
-        self.y = float(self.rect.y)
-
-        # 设置子弹颜色及速度(从ai_settings中读取)
-        self.color = ai_settings.bullet_color
-        self.speed_factor = ai_settings.bullet_speed_factor
-
-
-    def update(self):
-        """向上移动子弹"""
-        self.y -= self.speed_factor
-        self.rect.y = self.y
-
-
-    def draw_bullet(self):
-        """在屏幕上绘制子弹"""
-        pygame.draw.rect(self.screen, self.color, self.rect)