Collecting pip
  Downloading https://files.pythonhosted.org/packages/62/ca/94d32a6516ed197a491d17d46595ce58a83cbb2fca280414e57cd86b84dc/pip-19.2.1-py2.py3-none-any.whl (1.4MB)
    100% |████████████████████████████████| 1.4MB 1.6MB/s
mysql-connector-python 8.0.17 requires protobuf>=3.0.0, which is not installed.
Installing collected packages: pip
  Found existing installation: pip 10.0.1
    Uninstalling pip-10.0.1:
      Successfully uninstalled pip-10.0.1
Successfully installed pip-19.2.1

以上是我在powershell里面输入指令后，显示的信息，mysql-connector-python 8.0.17 requires protobuf>=3.0.0这个东西去哪里安装呀？