之前在网上找了各种资料，cmd安装yaml，网上大部分写的都是pip install yaml

ERROR: Could not find a version that satisfies the requirement yaml (from versions: none) ERROR: No_python

可是，执行完就变成Could not find a version that satisfies the requirement yaml No matching distribution found for yaml.

ERROR: Could not find a version that satisfies the requirement yaml (from versions: none) ERROR: No_各种资料_02

但是执行pip install pyyaml

ERROR: Could not find a version that satisfies the requirement yaml (from versions: none) ERROR: No_各种资料_03

就可以成功。
ERROR: Could not find a version that satisfies the requirement yaml (from versions: none) ERROR: No_各种资料_04

后来才知道，python3.X只能使用pip install pyyaml 来安装。

想要看安装是否成功，输入import pyyaml即可。