<button name="refuse_reason_action" string="Yes" type="object" class="oe_highlight"/>

class HrAppRefuseWiz(models.TransientModel): 

 _name = 'hr.applicant.refuse.wizard'

 refuse_reason = fields.Text('Refuse Reason')

@api.multi

def refuse_reason_action(self): 

if self: 

code logic 

when i put method my module stock working when i comment code of method where i'm wrong ....