code: func (config *DeferredLoadingClientConfig) ClientConfig() (*restclient.Config, error) {
  	mergedClientConfig, err := config.createClientConfig()
  	if err != nil {
  		return nil, err
  	}
  
  	// load the configuration and return on non-empty errors and if the
  	// content differs from the default config
  	mergedConfig, err := mergedClientConfig.ClientConfig()
  	switch {
  	case err != nil:
  		if !IsEmptyConfig(err) {
  			// return on any error except empty config
  			return nil, err
  		}
  	case mergedConfig != nil:
  		// the configuration is valid, but if this is equal to the defaults we should try
  		// in-cluster configuration
  		if !config.loader.IsDefaultConfig(mergedConfig) {
  			return mergedConfig, nil
  		}
  	}
  
  	// check for in-cluster configuration and use it
  	if config.icc.Possible() {
  		klog.V(4).Infof("Using in-cluster configuration")
  		return config.icc.ClientConfig()
  	}
  
  	// return the result of the merged client config
  	return mergedConfig, err
  }
docs: // ClientConfig implements ClientConfig