```

operating_unit = fields.Many2one('operating.unit', string='Operating Unit', default=lambda self: self._get_default_opr_unit())

@api.model 

 def _get_default_opr_unit(self): 

 return self.env['ir.default'].sudo().get('res.config.settings', 'operating_unit' or False)

@api.multi 

 @api.onchange('operating_unit') 

def _operating_unit_onchange(self): 

 if self.operating_unit: 

 return {'domain': {'adjustment_journal_id': [('operating_unit_id.id', '=', self.operating_unit.id)]}} 

 else: return {'domain': {'adjustment_journal_id': [('operating_unit_id.id', '=', False)]}}

```

when i load my wizard default value fill correctly but auto run my onchange method why ? 
i want to run my method when i change my field not auto  

where i'm wrong ?