由于环境错误而无法安装软件包：404客户端错误

Question

如何解决以上错误？

Answer 1

您缺少-r命令标志，因此请再次输入

 pip install -r requirements.txt

像以前一样，pip只是尝试从远程存储中获取requirements.txt，希望它是程序包名称。

请参见pip help install

用法：

pip install [options] <requirement specifier> [package-index-options]...
pip install [options] -r <requirements file> [package-index-options]...

...

pip also supports installing from "requirements files", which 
provide an easy way to specify a whole environment to be installed.

安装选项：

-r, --requirement <file>    Install from the given requirements file. 
                            This option can be used multiple times.

Answer 2

语法为pip install -r requirements.txt

Install Options:
  -r, --requirement <file>    Install from the given requirements file. This option can be used multiple times.