input: Write a python function to create an animated GIF from a list of image file paths.
  assert animateGif(['image1.png', 'image2.png', 'image3.png'], 'output.gif', 0.1) == None
  assert animateGif(['frame1.jpg', 'frame2.jpg'], 'animation.gif', 0.2) == None
output: def animateGif(image_paths, output_path, duration):
      from PIL import Image
      images = [Image.open(image) for image in image_paths]
      images[0].save(output_path, save_all=True, append_images=images[1:], duration=duration*1000, loop=0)