windows安装flask报错
输入 pip install -U Flask报错
distributed 1.21.8 requires msgpack,which is not installed
you are using pip version 10.0.1,however version 19.0.3 is available.
you should consider upgrading via the ‘python -m pip install --upgrade pip’ command.
分布式1.21.8需要MSGPack，但未安装
您使用的是10.0.1版PIP，但是19.0.3版可用。
您应该考虑通过“python-m pip install–upgrade pip”命令进行升级。
输入命令 python-m pip install–upgrade pip 更新python
重新输入pip install -U flask 成功