[O] How to access tables headers from within code block?

[Andreas Hilboll]

Hi,

I have a table like this
#+TBLNAME: t_tracers
| Trace gas | SCIATRAN alias |
|-----------+----------------|
| O3        | O3             |
| NO2       | NO2            |
| HCHO      | HCHO           |
| CHOCHO    | NO3            |
| HONO      | OCLO           |
| BRO       | BRO            |
| H2O       | H2O            |
| O4        | O4             |

and want to access the data from within a Python code block:

#+BEGIN_SRC python :var tracers_raw=t_tracers
return (tracers_raw)
#+END_SRC

My problem is that the table headers are apparently not passed to 
Python, as my results look like this:

#+RESULTS:
| O3     | O3   |
| NO2    | NO2  |
| HCHO   | HCHO |
| CHOCHO | NO3  |
| HONO   | OCLO |
| BRO    | BRO  |
| H2O    | H2O  |
| O4     | O4   |

How can I access the table headers also from within the code block?

Thanks for you help,
  Andreas.