Problem to save bank account on Demo6.4

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The bank account works on Demo6.2 and 5.8.

But a new bank account can not save on Demo6.4

Error message

[ced (Cédric Krier)]

Please report a bug.

PS: copy/paste the traceback so it can be indexed

[ced (Cédric Krier)]

For the record: Crash when saving bank account without IBAN (#11651) · Issues · Tryton / Tryton · GitLab

[txn (tangxn)]

https://codereview.tryton.org/411601003/diff/443471003/bank.py