http://conda.pydata.org/docs/test-drive.html

Install a different version of Python
conda create --name py2 python=2

Verify environment added
conda info --envs

Use a different version of Python
-Linux, OS X:

source activate py2

-Windows:

activate py2

Deactivate this environment
-Linux, OS X:

source deactivate

-Windows:

deactivate

Verify current environment
conda info --envs
# conda environments:
#
py2                   *  D:\Anaconda3\envs\py2
root                     D:\Anaconda3

Verify Python version in new environment
python --version

Update * to the current version
conda update *

remove package *
conda remove *

Change jupyter notebook environment
1.open Anaconda 
2.change Application on: py2 
3.install jupyter notebook
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作者：OoFrizyoO 
來源：CSDN 
原文：https://blog.csdn.net/u011291667/article/details/53717263?utm_source=copy