For reference, a correct #4 would read:

  with open("one_liners.py") as f: print f.readlines()

In CPython, a file handle is closed immediately the file goes out of scope, because it's reference-counted. In Jython (and I believe IronPython too), with lazier garbage collection, the filehandle would stay open until it was gc'd. I have no idea about PyPy's behaviour.