code: def get_model_head(name: str):
      """
      Given the model head name, construct the head if it's registered
      with VISSL.
      """
      assert name in MODEL_HEADS_REGISTRY, f"Unknown model head {name}"
      return MODEL_HEADS_REGISTRY[name]
  
file_path: vissl/vissl/models/heads/__init__.py
imports: from pathlib import Path
  from typing import Callable
  from classy_vision.generic.registry_utils import import_all_modules
  from vissl.models.heads.linear_eval_mlp import LinearEvalMLP
  from vissl.models.heads.mlp import MLP
  from vissl.models.heads.siamese_concat_view import SiameseConcatView
  from vissl.models.heads.swav_prototypes_head import SwAVPrototypesHead
  from vissl.models.heads.dino_head import DINOHead
label_desc: Use image node_id 2 for calling a global function with example usage: get_model_head(name) and returns: MODEL_HEADS_REGISTRY