创建环境:
conda create -n env_name python=3.7
显示所有环境：
conda env list
切换到某个环境:
source activate env_name
查看config：
conda config --show
换回默认源：
conda config --remove-key channels
遇到warning: possible package resolutions (only showing differing packages):
conda update --strict-channel-priority --all
遇到卡在Solving environment: done不动：
conda clean --all
