问题: clone conda环境时，pip命令无法使用。报错信息如下：
(ms) root@localhost:/home# pip list
Traceback (most recent call last):
  File "/home/miniconda3/envs/ms/bin/pip", line 7, in <module>
    from pip._internal import main
  File "/home/miniconda3/envs/ms/lib/python3.7/site-packages/pip/_internal/__init__.py", line 42, in <module>
    from pip._internal import cmdoptions
  File "/home/miniconda3/envs/ms/lib/python3.7/site-packages/pip/_internal/cmdoptions.py", line 16, in <module>
    from pip._internal.index import (
ImportError: cannot import name 'FormatControl' from 'pip._internal.index' (/home/miniconda3/envs/ms/lib/python3.7/site-packages/pip/_internal/index/__init__.py)


原因: 源conda环境存在两个pip，clone的是10.0.1版本。
(ms) root@localhost:/home# conda list|grep pip
pip                       10.0.1                   py37_0    c4aarch64
pip                       20.1.1                    <pip>


解决方法: 
source /home/miniconda3/bin/activate ci
conda install pip==20.1.1
conda create -n ms --clone ci