code: def register(self, what, obj):
          
          # print("Registering pattern", name, pattern)
          name = obj.name
          version = obj.version
          enable = obj.enable
          if enable == 'n':
              return
  
          key = Key(name, version)
          self.plugins[what][key] = obj
docs: Registering a plugin
  
          Params
          ------
          what: Nature of the plugin (backend, instrumentation, repo)
          obj: Instance of the plugin