tensorflow: tf.add_to_collection 探究

  def add_to_collection(self, name, value):
    """Stores `value` in the collection with the given `name`.
    Note that collections are not sets, so it is possible to add a value to
    a collection several times.
    Args:
      name: The key for the collection. The `GraphKeys` class
        contains many standard names for collections.
      value: The value to add to the collection.
    """
    self._check_not_finalized()
    with self._lock:
      if name not in self._collections:
        self._collections[name] = [value]
      else:
        self._collections[name].append(value)