Days ago, I thought anaconda could separate different python environment, so I created a new conda environment to install new version pip package. And no doubt, it failed.

The fact is: conda could only separate different conda package environment, not pip package. To separate the pip environment, we need to use virtualenv.

# Create new env
virtualenv -p /home/my/anaconda3/bin/python3.6 venv_my
# Enter the new env
source venv_my/bin/activate