Do not edit these templates directly! Apple usually automatically deletes them when upgrading to the next version of Xcode ...
Instead, you want to copy / paste them into:
~/Library/Developer/Xcode/
eg:.
~/Library/Developer/Xcode/File Templates/ ~/Library/Developer/Xcode/Project Templates/
... and then edit them there. Xcode knows what it should look there for your custom versions, and Apple will leave the contents of your home directory.
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