I have a py file and have set some read only states like this

READONLY_STATES = {

'waiting_admin_approval': [('readonly', True)], 

'done': [('readonly', True)],

'cancel': [('readonly', True)],

}

I have applied this states to the order line and it works fine.  But I need to make the field editable to the purchase manager and read only to the sales person when the order is in the 'waiting_admin_approval' state. 

Is it possible to update the state or override the state value in the view file ?

Thanks in advance.