I'm using pythran to convert my python+numpy code into C++, so far everything works really well with very efficient resulting code. However, my code requires the use of numpy.ffr.rfft and irfft (Fast Fourier Transform), which pythran apparently does not support:

```
import numpy as np
# pythran export testFunc(float[])
def testFunc(signal):
X = np.fft.rfft(signal,n=1024)
>pythran Foo.py
CRITICAL I am in trouble. Your input file does not seem to match
Pythran's constraints...
E: Attribute 'fft' unknown (Foo.py, line 5)
```

How could I possibly make this happen? If I call a C implementation of the fast fourier transform from the python code (I know this can be done) will pythran use that or will it complain about it?

EDIT: I compiled a simple C function into an so module which I can then call from my python code. All this works fine when invoked from python, but pythran does not work on the import:

```
CRITICAL I've got a bad feeling about this...
E: source code not available
```

So it looks like pythran does not work well with compiled .so files.