在python中从文件路径修改文件名的最佳方法是什么？

import os

def rename_file(old_path, new_name):
    # 获取文件所在的目录
    directory = os.path.dirname(old_path)
    # 构造新的文件路径
    new_path = os.path.join(directory, new_name)
    # 重命名文件
    os.rename(old_path, new_path)
    return new_path

# 使用示例
old_file_path = '/path/to/your/file.txt'
new_file_name = 'new_file_name.txt'
new_file_path = rename_file(old_file_path, new_file_name)
print(f'File has been renamed to: {new_file_path}')

import os

def rename_file(old_path, new_name):
    if not os.path.exists(old_path):
        raise FileNotFoundError(f"The file {old_path} does not exist.")
    
    directory = os.path.dirname(old_path)
    new_path = os.path.join(directory, new_name)
    
    if os.path.exists(new_path):
        raise FileExistsError(f"The file {new_path} already exists.")
    
    os.rename(old_path, new_path)
    return new_path

# 使用示例
try:
    old_file_path = '/path/to/your/file.txt'
    new_file_name = 'new_file_name.txt'
    new_file_path = rename_file(old_file_path, new_file_name)
    print(f'File has been renamed to: {new_file_path}')
except (FileNotFoundError, FileExistsError) as e:
    print(e)