change images to RGB

import os
from PIL import Image
import sys
def change_image_channels(input_image_path):
    image = Image.open(input_image_path)
    if image.mode == 'RGBA':
        r, g, b, a = image.split()
        image = Image.merge("RGB", (r, g, b))
        try:
            os.remove(input_image_path)
        except:
            pass
        image.save(input_image_path)
    elif image.mode != 'RGB':
        image = image.convert("RGB")
        try:
            os.remove(input_image_path)
        except:
            pass
        image.save(input_image_path)
    else:
        pass
    return image

if __name__ == "__main__":
    input_dir = sys.argv[1]
    for root, dirs, files in os.walk(input_dir):
        for file in files:
            path = os.path.join(root, file)
            change_image_channels(path)