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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def write_config(cfg):
    '''try writing config file to a default directory'''
    cfg_path = '/usr/local/etc/freelan'
    cfg_file = 'freelan_TEST.cfg'

    cfg_lines = []

    if not isinstance(cfg, FreelanCFG):
        if not isinstance(cfg, (list, tuple)):
            print("Freelan write input can not be processed.")
            return
        cfg_lines = cfg
    else:
        cfg_lines = cfg.build()

    if not os.path.isdir(cfg_path):
        print("Can not find default freelan config directory.")
        return

    cfg_file_path = os.path.join(cfg_path,cfg_file)

    if os.path.isfile( cfg_file_path ):
        print("freelan config file already exists - moving to not replace content.")
        ts = time.time()
        backup_file = cfg_file_path+'.ORG-'+datetime.datetime.fromtimestamp(ts).strftime('%y-%m-%d-%H-%M-%S')
        shutil.move(cfg_file_path, backup_file)

    cfg_lines = [cfg_line+'\n' for cfg_line in cfg_lines]

    with open(cfg_file_path, 'w') as cfg_f:
        cfg_f.writelines(cfg_lines)