I don't know if it'll work for Python, but here's an example of what
works for me with Ditaa:

> #+BEGIN_SRC ditaa :file figs/-mininet-ovsk.png :cache yes
>    /----+ /----+ /----+ /----+
>    |host| |host| |host| |host|       Containers
>    +-+--/ +-+--/ +--+-/ +--+-/
>      |      |       |      |
>   ---------------------------------------------
>      |      |       |      |
>    +-+------+-------+------+-+
>    |      Open VSwitch       |      Host kernel
>    +-----+-------------+---=-+
>          |             |
>   +------+-----+ +-----+------+
>   | controller | | controller |  Host userspace
>   +------------+ +------------+
> #+END_SRC
> 
> #+ATTR_LATEX: :width "" :options [scale=0.75]
> #+CAPTION: [[label:fig:mininet-arch]]Mininet with OpenVSwitch architecture
> #+RESULTS[1d367d39f18523f4eb247cb13aabd6c6f633fbdf]: [[file:figs/-mininet-ovsk.png]]

First, execute your Babel block in order to generate a #+RESULTS line.
Then, add CAPTION, ATTR_LATEX etc. lines before the RESULTS line.

Good luck!
Georgiy

On 30 Aug, Florian Lindner wrote:
> Hello,
> 
> I have this code block:
> 
> #+BEGIN_SRC python :exports results :results file
>   import matplotlib.pyplot as plt, numpy as np
>   x = np.linspace(-2, 2, 1000)
>   plt.plot(x, np.exp(-np.power(4*x, 2)), label="shape-parameter=4")
>   for i in range(-4, 5): plt.axvline(1/6 * i, ymax = 0.1, ls = "-.", color="r")
>   plt.grid()
>   plt.savefig('rbf-gaussian-4.pdf')
>   return "rbf-gaussian-4.pdf"
> #+END_SRC
> 
> When exporting to latex it nicely compiles into \includegraphics[width=.9\linewidth]{rbf-gaussian-4.pdf}.
> 
> Now I want to have this \includegraphics in a figure environement including a label (to reference it) and a caption.
> 
> How can do this best?
> 
> I have found:
> http://emacs.stackexchange.com/questions/12150/add-caption-to-an-image-generated-by-a-code-block
> 
> but it doesn't work for me.
> 
> Thanks,
> Florian
> 
>