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Cell Tags From In/Out Names

▪ Cell Tags From In/Out Names gives the selected cell a tag that is the same as its current input or output prompt.
▪ Ordinarily, Mathematica's In[]:=Italic and Out[]=Italic prompts (CellLabels) disappear when you close a notebook. That is because the numbers associated with input and output cells are only relevant during a particular Mathematica session.
▪ If you want to preserve the In/Out prompts in your notebook, perhaps for publication reasons, you can make them into cell tags and then show the cell tags.
▪ This command also allows you to locate particular In/Out lines by using the Cell Tags submenu.