code: def defaults(cls, *options, **kwargs):
          
          if kwargs and len(kwargs) != 1 and list(kwargs.keys())[0] != 'backend':
              raise Exception('opts.defaults only accepts "backend" keyword argument')
  
          cls._linemagic(cls._expand_options(merge_options_to_dict(options)), backend=kwargs.get('backend'))
docs: Set default options for a session.
  
          Set default options for a session. whether in a Python script or
          a Jupyter notebook.
  
          Args:
             *options: Option objects used to specify the defaults.
             backend:  The plotting extension the options apply to