[O] Problem with code blocks and new exporter

[Richard Stanton]

I'm having trouble exporting code blocks with the new exporter. I'm sure
I've missed something obvious, but can anyone tell me why the following
file doesn't work exporting to LaTeX or HTML?

-----------

Code snippet:

#+begin_src python
a = 5
#+end_src python

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When I export this, I don't get a code block displayed. Instead, I get a
single line that includes the text "#+begin_src", which is not what I
wanted (or what I was expecting). What am I doing wrong...?

Thanks very much.

Richard Stanton