code: def RetrievePluginAsset(self, run, plugin_name, asset_name):
      
      accumulator = self.GetAccumulator(run)
      return accumulator.RetrievePluginAsset(plugin_name, asset_name)
docs: Return the contents for a specific plugin asset from a run.
  
      Args:
        run: The string name of the run.
        plugin_name: The string name of a plugin.
        asset_name: The string name of an asset.
  
      Returns:
        The string contents of the plugin asset.
  
      Raises:
        KeyError: If the asset is not available.