[pygtk] pygtkscintilla, setting style.

[M.B.]

hi all, 
i am trying now 'pygtksci'.
i create pygtkscintilla.Scintilla object like in test.py
but how i change font for empty [without any character] clean object
where all style will be applied on whole text which i write ?

a = Source() # this is my object same as in test.py from pygtksci
a.set_style(1, color="Blue", font="!Terminus 8')
a.apply_style(1, 0, 3)  # crash. cannot apply style coz object is empty

Assertion [lengthStyle == 0 || (lengthStyle > 0 && lengthStyle +
position <= style.Length())] failed at ../scintilla/src/CellBuffer.cxx
399

thanks a lot.