Batch mode evaluation of source code?

[Herbert Sitz <hsitz@nwlink.com>]

The Org manual gives an example of a batch mode --eval that runs code to tangle
code from Org files.  I assume there's also a way to simply run a source code
block and get its output in the terminal but I can't see how to do it.

To give a concrete example, the Org manual uses this Python source block as
example illustrating the difference between :session and non-session results
output.  How would I evaluate it from the command line and get the results
output back in the terminal?:

-------------------------
#+begin_src python  :results output
print "hello"
2
print "bye"
#+end_src
------------------------

-- Herb