# optional authentication information
# either set it here or pass it in via the environment
# SMB_USER=
# SMB_PASSWORD
    

I don't think that embedding password information in a distributed
example program map is the right thing to do. People need to work out
how they will access authentication information for themselves and
modify the example program map to suite.

Also, I don't understand how this can be set in the environment. If it
is set in the daemon environment, typically root, and used for every
mount then I don't think that is a good example of usage to distribute
either.
  
This is just how I do it and thought it might help others who are perhaps wondering how to do it
I did miss out one line - which is what you are puzzling over.
I include another script which contains SMB_USER and SMB_PASSWORD into the environment
I have the line
. /etc/my_user_info
in my version of the script
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