I want to set hundreds of account move lines of one specific account to draft status.

I created a contextual action based on mass cancel/draft for journal entries, but I cannot find the right command for mass drafting multiple account move lines.

The error message states: 

AttributeError: 'account.move.line' object has no attribute 'abc'

For mass drafting journal entries, this code works:

for record in records:

    record.button_draft()

What is the correct code for account move lines?