class_docstr: List-like object to hold immutable latent state.
  
  This must either be given a name when constructed::
  
      latent = named.List("root")
  
  or must be immediately stored in a ``named.Object``::
  
      latent = named.Object("root")
      latent.xs = named.List()  # Must be bound to a Object before use.
  
  .. warning:: This data structure is write-once: data may be added but may
      not be mutated or removed. Trying to mutate this data structure may
      result in silent errors.
code: def __init__(self, name=None):
      self._name = name
  
imports: import functools
  import pyro
label_desc: Use image node_id 1 to create a new List object from inherited base classes: list with example: obj = List(name)