Some changes...

Animation.py

@@ -0,0 +1,27 @@
+import pygame
+
+class Animation(object):
+    def __init__(self, image, start_x, start_y, num, width, height, duration) -> None:
+        self.image = image
+
+        self.start_x = start_x
+        self.start_y = start_y
+        self.num = num
+        self.width = width
+        self.height = height
+
+        self.duration = duration
+        self.time = 0
+        self.current = 0
+
+    def render(self, screen, pos):
+        screen.blit(self.image, pos, pygame.Rect(self.start_x + (self.width * self.current), self.start_y, self.width, self.height))
+
+    def update(self, time=1):
+        self.time += time
+
+        if self.time > self.duration:
+            self.time = 0
+            self.current += 1
+            if self.current >= self.num:
+                self.current = 0