None check k.name; iso import

[pvgenuchten]

Overview

previous fix unfortunately did not solve the issue,
the issue was not related to all-keywords being empty, but inside the keywords array, keyword.name being None.
this PR removes the None check for all-keywords, and adds None check for k.name

reproduce error by:

','.join(['a',None,'b'])

Related Issue / Discussion

#1019

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