title: This Bazel build file has only deps no srcs
body: <p>I was trying to use google's media pipe but this Bazel build has no srcs only deps. What is supposed to be the main program in this build?</p>
  
  <pre><code>package(default_visibility = ["//mediapipe/examples:__subpackages__"])
  
  cc_binary(
      name = "hand_tracking_tflite",
      deps = [
          "//mediapipe/examples/desktop:simple_run_graph_main",
          "//mediapipe/graphs/hand_tracking:desktop_tflite_calculators",
      ],
  )
  
  cc_binary(
      name = "hand_tracking_cpu",
      deps = [
          "//mediapipe/examples/desktop:demo_run_graph_main",
          "//mediapipe/graphs/hand_tracking:desktop_tflite_calculators",
      ],
  )
  
  # Linux only
  cc_binary(
      name = "hand_tracking_gpu",
      deps = [
          "//mediapipe/examples/desktop:demo_run_graph_main_gpu",
          "//mediapipe/graphs/hand_tracking:mobile_calculators",
      ],
  )
  </code></pre>