class_docstr: Class for registry object which acts as central source of truth
  for MMF
code: def get_encoder_class(cls, name):
      return cls.mapping["encoder_name_mapping"].get(name, None)
  
imports: from mmf.utils.env import setup_imports
label_desc: Use image node_id 33 for calling the Registry obj's underlying member method code with example usage: obj.get_encoder_class(cls, name) and returns: cls