code: def _register_conversion_function_once():
      """Performs one-time registration of `_lazy_tensor_creator_converter`.
  
      This helper can be invoked multiple times but only registers the conversion
      function on the first invocation, making it suitable for calling when
      constructing a LazyTensorCreator.
  
      Deferring the registration is necessary because doing it at at module import
      time would trigger the lazy TensorFlow import to resolve, and that in turn
      would break the delicate `tf.summary` import cycle avoidance scheme.
      """
      global _conversion_registered
      if not _conversion_registered:
          with _conversion_registered_lock:
              if not _conversion_registered:
                  _conversion_registered = True
                  tf.register_tensor_conversion_function(
                      base_type=LazyTensorCreator,
                      conversion_func=_lazy_tensor_creator_converter,
                      priority=0,
                  )
  
imports: import threading
  from tensorboard.compat import tf2
label_desc: Use image node_id 2 for calling a global function with example usage: _register_conversion_function_once() without return types