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I have a problem with Python script in Field Calculator. How to sum the values of one field ('AB') and paste the sum in another field ('RE') using Python in Field Calculator? I'm working in ArcMap 10.5.1. (Python 2.7) enter image description here

What should I write in CodeBlock and after RE= ? ![enter image description here

marked as duplicate by Hornbydd arcgis-desktop Mar 26 at 12:12

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