Meeting App: unexpected-keyword-argument-bulk

I tried Meeting App: GitHub - frappe/meeting: Prepare agenda, invite users and record minutes of a meeting in ERPNext 12, after creating a new meeting ib trying to send email to attendee, it through error:

TypeError: sendmail() got an unexpected keyword argument ‘bulk’

I also found a similar error:

TypeError: sendmail() got an unexpected keyword argument ‘bulk’

with solution at: TypeError: sendmail() got an unexpected keyword argument 'bulk' - #2 by vjFaLk

But could not find any file where I could change such line of code.

May I get any hint, to remove this argument.

Found. It is at: