list index out of range

[开阖软件 Jeff Wang]

    def move_line_on_change(self, cr, uid, ids, lines):
        lines_default_value = False
# if lines[0][2]:
        if lines and lines[0][2]:
            lines_default_value = lines[0][2].get('name', False)
        return {'value':{'lines_default_value':lines_default_value}}

in oecn_account_print/account.py line 43