New function add_picture

[tvso]

• Update unit tests and docs for the function
• Add example code in the README

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (da94b03) to head (3ca1079).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main        #3   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            4         4           
  Lines          696       706   +10     
=========================================
+ Hits           696       706   +10     

Flag	Coverage Δ
unittests	100.00% <100.00%> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[xuri]

LGTM, thanks for your contribution.