Python: lsm image to tif image

import tifffile, cv2, os
List_dir = "lsm/"
out_dir = "out/"
LSM_list = [i for i in os.listdir(List_dir) if ".lsm" in i]
LSM_list[0]

for i in LSM_list:
    A = tifffile.imread(List_dir + i)
    #fig, ax = plt.subplots(figsize=(10, 10))
    for ch_id in range(A.shape[1]):
        Pic = A[:,ch_id,:,:]
        tifffile.imsave(out_dir + i+str(ch_id)+".tif", Pic)