class_docstr: Class raising error if used
  
  Standard use is to proxy modules that we could not import
  
  Examples
  --------
  >>> try:
  ...     import silly_module_name
  ... except ImportError:
  ...    silly_module_name = TripWire('We do not have silly_module_name')
  >>> silly_module_name.do_silly_thing('with silly string') #doctest: +IGNORE_EXCEPTION_DETAIL
  Traceback (most recent call last):
      ...
  TripWireError: We do not have silly_module_name
code: def __init__(self, msg):
      self._msg = msg
  
label_desc: Use image node_id 1 to create a new TripWire object  with example: obj = TripWire(msg)