@api.onchange('applicant_credential_id') 

 def _onchnage_applicant_credential_id(self): 

 res = {} 

 for rec in self: 

 if rec.applicant_credential_id: 

 rec.partner_name = rec.applicant_credential_id.full_name 

 rec.readonly_partner_name = True

 res['attrs']={'partner_name':{'invisible': [('readonly_partner_name', '=', True)]}} 

 else: 

 rec.readonly_partner_name = False 

 res['attrs']={'partner_name':{'invisible': [('readonly_partner_name', '=', False)]}} 

 return res
​

code is not working how i can write 

res['attrs']={'partner_name':{'invisible': [('readonly_partner_name', '=', False)]}} 

where is my mistake ?