code: def create(cls, schema, name):
          
          fn = cls.tags.get(name, XBuiltin)
          return fn(schema, name)
docs: Create an object based on the root tag name.
  
          @param schema: A schema object.
          @type schema: L{schema.Schema}
          @param name: The name.
          @type name: str
          @return: The created object.
          @rtype: L{XBuiltin}