docs: def clean(self, *args, **kwargs):
          """
          Check if votes can be inserted for parent node or parent layer
          """
          if not self.pk:
              # ensure voting for this node is allowed
              if self.node.participation_settings.voting_allowed is not True:
                  raise ValidationError("Voting not allowed for this node")
  
              if 'nodeshot.core.layers' in settings.INSTALLED_APPS:
                  layer = self.node.layer
  
                  # ensure voting for this layer is allowed
                  if layer.participation_settings.voting_allowed is not True:
                      raise ValidationError("Voting not allowed for this layer")