Python已安装,但在Windows命令提示符下为空白

I have installed Python and clicked the add to PATH button and have installed PyCharm and it works. However whenever I go to type python --version in the windows command prompt it comes up blank? Also not Showing command not found

我之前已经运行过程序,并且一切正常。但我只是不知道为什么它不能在Windows中工作。 这是我的PATH变量: