https://community.esri.com/t5/python-questions/python-tool-error/m-p/1193726#M65018 <P>I created a python script for ArcGIS Pro tool I created. It worked fine a week ago, but for some reason, it now has this error: "ERROR 032659...TypeError: unsupported operand type(s) for +: 'NoneType' and 'str'." What does this error mean and what are some possibilities for this type of error?&nbsp;</P><P>Thanks ahead for your help!</P> Tue, 19 Jul 2022 23:22:01 GMT tzz_12 2022-07-19T23:22:01Z https://community.esri.com/t5/python-questions/python-tool-error/m-p/1193726#M65018 <P>I created a python script for ArcGIS Pro tool I created. It worked fine a week ago, but for some reason, it now has this error: "ERROR 032659...TypeError: unsupported operand type(s) for +: 'NoneType' and 'str'." What does this error mean and what are some possibilities for this type of error?&nbsp;</P><P>Thanks ahead for your help!</P> Tue, 19 Jul 2022 23:22:01 GMT https://community.esri.com/t5/python-questions/python-tool-error/m-p/1193726#M65018 tzz_12 2022-07-19T23:22:01Z https://community.esri.com/t5/python-questions/python-tool-error/m-p/1193739#M65019 <P>It means that whatever line was trying to concatenate two things that were expecting strings and the first was "None"</P><LI-CODE lang="python">a = None; b = "something" a + str(b) Traceback (most recent call last): File ",,,1.py", line 1, in &lt;cell line: 1&gt; a + str(b) TypeError: unsupported operand type(s) for +: 'NoneType' and 'str'</LI-CODE><P>Now you can fix it without solving the None problem by using</P><LI-CODE lang="python">f"{a} + {b}" 'None + something' f"{a}{b}" 'Nonesomething' "{}{}".format(a, b) 'Nonesomething'</LI-CODE><P>You will have to figure out why the first variable isn't getting what you want</P> Wed, 20 Jul 2022 00:15:17 GMT https://community.esri.com/t5/python-questions/python-tool-error/m-p/1193739#M65019 DanPatterson 2022-07-20T00:15:17Z