code: @BetaApi
    public final Operation switchToCustomModeNetwork(String network) {
  
      SwitchToCustomModeNetworkHttpRequest request =
          SwitchToCustomModeNetworkHttpRequest.newBuilder().setNetwork(network).build();
      return switchToCustomModeNetwork(request);
    }
docs: Switches the network mode from auto subnet mode to custom subnet mode.
  
  <p>Sample code:
  
  <pre><code>
  try (NetworkClient networkClient = NetworkClient.create()) {
  ProjectGlobalNetworkName network = ProjectGlobalNetworkName.of("[PROJECT]", "[NETWORK]");
  Operation response = networkClient.switchToCustomModeNetwork(network.toString());
  }
  </code></pre>
  
  @param network Name of the network to be updated.
  @throws com.google.api.gax.rpc.ApiException if the remote call fails