Hi i want to hide a button on a user

I create a boolean field 

user_id = fields.Many2one('res.users', 'User', related='resource_id.user_id')
current_user = fields.Boolean('is current user ?', compute='_get_current_user')

@api.depends('user_id')
def _get_current_user(self):
for e in self:
    e.current_user = (True if e.env.user.id == e.user_id.id else False)

<xpath expr="//button[@name='action_view_picking']"  position="attributes">

             <attribute name="attrs">{'invisible':[('current_user', '=', False)]}</attribute>

   </xpath>

but it does not work

Field 'current_user' used in attributes must be present in view but is missing:

 - 'current_user' in attrs="{'invisible':[('current_user', '=', False)]}"