class_docstr: MetadataCatalog provides access to "Metadata" of a given dataset.
  
  The metadata associated with a certain name is a singleton: once created,
  the metadata will stay alive and will be returned by future calls to `get(name)`.
  
  It's like global variables, so don't abuse it.
  It's meant for storing knowledge that's constant and shared across the execution
  of the program, e.g.: the class names in COCO.
docstr: Remove all registered metadata.
docstr_tok: ["Remove","all","registered","metadata","."]
code: def clear():
      """
      Remove all registered metadata.
      """
      MetadataCatalog._NAME_TO_META.clear()
  
imports: import copy
  import logging
  import types
  from typing import List
label_desc: Use image node_id 3 for calling the MetadataCatalog obj's underlying member method code with example usage: obj.clear() without return types