重装系统后安装transformers遇到bug，记录一下，方面以后查看。

Windows下使用pip install transformers命令重新安装时，却报错：

error: can't find Rust compiler
      
    If you are using an outdated pip version, it is possible a prebuilt wheel is available for this package but pip is not able to install from it. Installing from the wheel would avoid the need for a Rust compiler.
      
    To update pip, run:
      
        pip install --upgrade pip
      
    and then retry package installation.
      
    If you did intend to build this package from source, try installing a Rust compiler from your system package manager and ensure it is on the PATH during installation. Alternatively, rustup (available at https://rustup.rs) is the recommended way to download and update the Rust compiler toolchain.
    [end of output]
  
note: This error originates from a subprocess, and is likely not a problem with pip.
ERROR: Failed building wheel for tokenizers
Failed to build tokenizers
ERROR: Could not build wheels for tokenizers, which is required to install pyproject.toml-based projects

根据错误提示，首先运行pip install --upgrade pip无效，然后便根据错误的提示需要安装Rust Compiler，首先去其官网下载相应的安装包，根据本人的实际情况选择64位的安装文件，然后点击下载的exe文件进行安装，安装过程中选择默认（default）配置即可。

根据官网的说明Rust所有的工具都在~/.cargo/bin目录，包括rustc、cargo和rustup命令，因此需要将其配置到环境变量中，但Windows会进行自动配置，但是配置的环境变量在Windows下需要重启电脑才会生效。在重启后，再次运行安装命令：

pip install transformers

结果是安装成功，截图如下：