rename_folders.py

import os

def rename_folders(path, dirs, src, dst):
    for name in os.listdir(path):
        if re.match(dirs, name):
            name2 = re.sub(src, dst, name)
            filepath1 = path + os.sep +  name
            filepath2 = path + os.sep + name2
            os.rename(filepath1, filepath2)
            
if __name__ == '__main__':            
  rename_folders(
        path='/Volumes/Bydle4TB/FILMY', 
        dirs=r'^\d{4} - ', 
        src=r'^(\d{4}) - (.+)',  
        dst=r'\2 (\1)'
  )