message: Better error message when we swap parameter to Session. I had this bug and search on the web do not bring good answer.
diff: @@ -648,6 +648,10 @@ class BaseSession(SessionInterface):
  try:
  self._target = compat.as_bytes(target)
  except TypeError:
  + if isinstance(target, config_pb2.ConfigProto):
  + raise TypeError('target must be a string, but got %s.'
  + ' Did you do "Session(config)" instead of'
  + ' "Session(config=config)"?' % type(target))
  raise TypeError('target must be a string, but got %s' % type(target))
  else:
  self._target = None
  