import os
import pkgutil
import fileinput
import sys

def replace_keyword_in_package_file(package_name, target_file, old_str, new_str):
    """
    替换指定包中某个文件的关键字
    
    参数:
        package_name (str): 要查找的包名
        target_file (str): 要替换的文件名(包括相对路径)
        old_str (str): 要被替换的关键字
        new_str (str): 替换后的新关键字
    """
    try:
        # 获取包的路径
        package = pkgutil.get_loader(package_name)
        if package is None:
            print(f"错误: 找不到包 '{package_name}'")
            return False
        
        package_path = os.path.dirname(package.get_filename())
        target_path = os.path.join(package_path, target_file)
        
        # 检查目标文件是否存在
        if not os.path.exists(target_path):
            print(f"错误: 文件 '{target_file}' 不在包 '{package_name}' 的路径中")
            return False
        
        # 执行替换操作
        print(f"正在处理文件: {target_path}")
        print(f"将 '{old_str}' 替换为 '{new_str}'")
        
        replaced = False
        with fileinput.FileInput(target_path, inplace=True, backup='.bak') as file:
            for line in file:
                if old_str in line:
                    replaced = True
                print(line.replace(old_str, new_str), end='')
        
        if replaced:
            print("替换完成!")
            return True
        else:
            print(f"警告: 文件中未找到关键字 '{old_str}'")
            return False
            
    except Exception as e:
        print(f"发生错误: {str(e)}")
        return False

replace_keyword_in_package_file("aioredis", "exceptions.py", "builtins.TimeoutError,", "")