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+This is the Git Repository to share the Jupyter Notebooks with the students.
+Its address is https://c4science.ch/source/quantum_optics2021.git
+
+IMPORTANT : I don't know how to make some files accessible and not others inside a given repo, so DON'T UPLOAD YOUR SOLUTION NOTEBOOKS !!
+
+When you need a notebook for an exercise class, create a subfolder for it, copy it in there.
+Then launch a bash in this main directory, and type :
+
+git add --all
+git commit -m 'exercise XXX'  (change to your exercise number)
+git push
+
+After that, anyone can launch the notebooke in Binder  at that URL :
+https://mybinder.org/v2/git/https%3A%2F%2Fc4science.ch%2Fsource%2Fquantum_optics2021.git/master
+
+For help, ask Hideki
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