code: def json_data(self, name):
          
  
          # Check the write permission of the context
          # XXX: This should be done on field level by the field manager adapter
          if not self.can_write():
              raise Unauthorized("You are not allowed to modify this content")
  
          # fetch the field by name
          field = api.get_field(self.context, name)
  
          # bail out if we have no field
          if not field:
              return None
  
          fieldmanager = IFieldManager(field)
          return fieldmanager.json_data(self.context)
docs: Get a JSON compatible structure for the named attribute