如何在matplotlib中将GIF动画写入文件式缓冲区？

import matplotlib.pyplot as plt
from matplotlib.animation import FuncAnimation
from PIL import Image

def update(frame):
    # 在此处更新图像
    return plt.imshow(frame)

frames = []

fig = plt.figure()
ani = FuncAnimation(fig, update, frames=range(10), blit=True)
for i in range(len(ani.frames)):
    frames.append(ani.frames[i])

# 使用ImageMagick
with Image() as img:
    img.sequence.extend(frames)
    img.save(filename='animation.gif')

# 使用Pillow
with Image.new('RGB', frames[0].size) as img:
    img.save(filename='animation.gif', save_all=True, append_images=frames[1:])