title: raise... from: use pdb to move into the stack of the wrapped exception
body: <p>Python 3 features the raises... from construct:</p>
  
  <pre><code>def f():
      assert False
  
  def g():
      try:
          f()
      except Exception as e:
          raise Exception('this is a wrapper') from e
  
  g()
  </code></pre>
  
  <p>The above prints out:</p>
  
  <pre><code>Traceback (most recent call last):
    File "raise_from.py", line 6, in g
      f()
    File "raise_from.py", line 2, in f
      assert False
  AssertionError
  
  The above exception was the direct cause of the following exception:
  
  Traceback (most recent call last):
    File "raise_from.py", line 10, in &lt;module&gt;
      g()
    File "raise_from.py", line 8, in g
      raise Exception('this is a wrapper') from e
  Exception: this is a wrapper
  </code></pre>
  
  <p>Which is very nice and neat.
  However, when I try debugging the program, either with command-line pdb or PyCharm, I cannot find any way to jump onto the stack of the wrapped exception. How do I retrieve the local variables of f() at the moment it raised the original AssertionError?</p>