Generates an EmptyTag token

        :arg namespace: the namespace of the token--can be ``None``

        :arg name: the name of the element

        :arg attrs: the attributes of the element as a dict

        :arg hasChildren: whether or not to yield a SerializationError because
            this tag shouldn't have children

        :returns: EmptyTag token

def emptyTag(self, namespace, name, attrs, hasChildren=False):
        """Generates an EmptyTag token

        :arg namespace: the namespace of the token--can be ``None``

        :arg name: the name of the element

        :arg attrs: the attributes of the element as a dict

        :arg hasChildren: whether or not to yield a SerializationError because
            this tag shouldn't have children

        :returns: EmptyTag token

        """
        yield {"type": "EmptyTag", "name": name,
               "namespace": namespace,
               "data": attrs}
        if hasChildren:
            yield self.error("Void element has children")