message: Handle None namespace in EAGER mode.
diff: @@ -4925,12 +4925,11 @@ def name_scope(name, default_name=None, values=None):
  """
  n = default_name if name is None else name
  if context.in_eager_mode():
  - if n is None:
  - raise ValueError(
  - "At least one of name (%s) and default_name (%s) should be provided" %
  - (name, default_name))
  ctx = context.context()
  old_name = ctx.scope_name
  + if n is None:
  + scope_name = ""
  + else:
  scope_name = "%s%s/" % (old_name, n) if old_name else "%s/" % n
  ctx.scope_name = scope_name
  try:
  