===== conda environment file to install different packages from different channels ====

==== Background ====

yfinance library is the easiest and fastest way to download historical stock prices. Asof 2023-05-20, it is not available in the defaults channel. But it is available in the conda-forge channel.

==== Task ====

The goal here is to pull the yfinance package from conda-forge but everything else from the defaults channel.

==== Solution ====

<code>
 % cat env_test_yfinance.yml | stuff.py
name: test_yfinance
channels:
  - defaults
dependencies:
  - python=3.11
  - conda-forge::yfinance
</code>

where stuff.py is a python script to strip out the comments. It can be downloaded from https://github.com/KamarajuKusumanchi/rutils/blob/master/python3/stuff.py

Create the environment

<code>
 % conda env create -f ./env_test_yfinance.yml
</code>

==== Evidence ====
yfinance is downloaded from conda-forge.
<code>
 % conda list -n test_yfinance | grep conda-forge
multitasking              0.0.9              pyhd8ed1ab_0    conda-forge
yfinance                  0.2.18             pyhd8ed1ab_0    conda-forge
</code>

python is downloaded from the defaults channel
<code>
 % conda list -n test_yfinance | grep "python"     
python                    3.11.3               h7a1cb2a_0  
python-dateutil           2.8.2              pyhd3eb1b0_0
</code>

==== See also ====
  * The above environment file can be downloaded from https://github.com/KamarajuKusumanchi/rutils/blob/master/python3/envs/env_test_yfinance.yml
  * I got the idea from https://stackoverflow.com/questions/58555389/set-the-channel-priority-in-conda-environment-yaml -> https://stackoverflow.com/a/65983247/6305733
  * The official documentation I could find on this feature is https://conda.io/projects/conda/en/latest/user-guide/tasks/manage-environments.html#creating-an-environment-file-manually \\ <Todo:- See if you can find a better link afterwards.>