print("--- AI训练常用工具 ---")          
tools = ["TensorFlow", "PyTorch", "Keras"]
print("初始工具列表:",  tools       )
print("当前工具数量:", len( tools )  )       
print("每个工具名称：")                  
for t in tools:                        
    print(" -",    t  )  
print("\n--- 添加新工具 ---")
new_tools = ["Scikit-learn", "MXNet"]
for tool in new_tools:
    if tool not in tools:
        tools.  append(tool)
    else:        
        print(f"工具 '{tool}' 已存在，跳过添加")

print("\n更新后的工具列表:",  tools )