custom code export / import error

this was a problem on 4.5 too
I exported the custom code so I could remove it all as part of the testing on the fatal error logging tests see other post

Both times I have tried this procedure on import this message comes up. And all I did was export and import.

Error: The cc-master.txt file MUST contain all of the BEGIN and END placeholder lines of code even if they are blank/do not have any custom code. Create a new Custom Code Export file and manually add/edit your additional custom code, BUT leave all of the BEGIN and END comment placeholder lines of code in the new cc-master.txt file that you Export.

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