code: def close(self):
      if self.closed is None:
          raise SerializerError("serializer is not opened")
      elif not self.closed:
          self.emit(StreamEndEvent())
          self.closed = True
  
file_path: catboost/contrib/python/PyYAML/py3/yaml/serializer.py
imports: from .error import YAMLError
  from .events import *
  from .nodes import *
label_desc: Use image node_id 3 for calling the Serializer obj's underlying member method code with example usage: obj.close() without return types