title: (Python) Why `getsource` method in `inspect` module returns error?
body: <p>I tried to apply <code>getsource</code> method in <code>inspect</code> module to <code>bisect_right</code> method in <code>bisect</code> module such as the following:</p>
  <pre><code>import inspect
  import bisect
  
  print(inspect.getsource(bisect.bisect_right))
  </code></pre>
  <p>Then, <code>getsource</code> returned the following error:</p>
  <pre><code>TypeError: module, class, method, function, traceback, frame, or code object was expected, got builtin_function_or_method
  </code></pre>
  <p>Why <code>getsource</code> returned the error?
  For example, the following code works.</p>
  <pre><code>import random
  import inspect
  
  print(inspect.getsource(random.randint))
  </code></pre>