title: What is the right way to refer bazel data files in python?
body: <p>Suppose I have the following <code>BUILD</code> file</p>
  
  <pre><code>py_library(
    name = "foo",
    src = ["foo.py"],
    data = ["//bar:data.json"],
  )
  </code></pre>
  
  <p>How should I refer to the <code>data.json</code> in <code>foo.py</code> file? I wanted to have something like below, what should I use for <code>some_path</code>?</p>
  
  <pre><code>with open(os.path.join(some_path, "bar/data.json"), 'r') as fp:
      data = json.load(fp)
  </code></pre>
  
  <p>I couldn't find much general documentation about <code>*.runfiles</code> online -- any pointer will be appreciated!</p>