I have created a report which is working fine (Accounting, Journal entries). What i want now is to get some data from other model (res.partner), so i need to call python function from qweb report, as i understand i need to make a custom report like in example here - https://www.odoo.com/documentation/9.0/reference/reports.html#custom-reports

So i did it all like in an example, but after installing my module with custom class im getting an error:

 "'report.l10n_lt_buh_aps_forma.report_buh_aps_forma_' object has no attribute 'line_ids'" while evaluating

'o.line_ids'

As i understand after installing module with this custom class i cant access all object attributes. Here is my code:

from openerp import api, models, fields
def some_math(txt):
    return txt * 5
def get_formato(self):
    return 'its working' 
class buh_aps_report(models.AbstractModel):
    _name = 'report.l10n_lt_buh_aps_forma.report_buh_aps_forma_lt'
    #_template = 'l10n_lt_buh_aps_forma.report_buh_aps_forma_lt'
    # _inherit = 'account.move'
    @api.multi
    def render_html(self, data=None):
        report_obj = self.env['report']
        report = report_obj._get_report_from_name('l10n_lt_buh_aps_forma.report_buh_aps_forma_lt')
        docargs = {
            'doc_ids': self._ids,
            'doc_model': report.model,
            'docs': self,
            'some_math': some_math,
            'get_formato': get_formato,
        }
        return report_obj.render('l10n_lt_buh_aps_forma.report_buh_aps_forma_lt', docargs)

Here is my template code:

<report 
            id="account.report_buh_aps"
            model="account.move"
            string="Buhalterinės apskaitos forma (EN text)"
            report_type="qweb-pdf"
            attachment_use="False"
            name="l10n_lt_buh_aps_forma.report_buh_aps_forma_lt"
            file="l10n_lt_buh_aps_forma.report_buh_aps_forma_lt"
        />

And i have to mention, that i have found some older way to for my problem, which is actually working:

class buh_aps_report(report_sxw.rml_parse):

      def __init__(self, cr, uid, name, context):
          super(buh_aps_report, self).__init__(cr, uid, name, context=context)
          self.localcontext.update({
                'time': time,
                'get_format':self.get_format,
                 })
 
     def get_format(self):
         return 'its working' 
 
 class report_saleorderqweb(models.AbstractModel):
     _name = 'report.l10n_lt_buh_aps_forma.report_buh_aps_forma_lt'
     _inherit = 'report.abstract_report'
     _template = 'l10n_lt_buh_aps_forma.report_buh_aps_forma_lt'
     _wrapped_report_class = buh_aps_report

As i understand second method is based on old API, so i would like to understand what i did wrong in first method, what is missing?

Im completely new to python and odoo, so any help will be appreciated, thank you