I want to build a mini markup mechanism for PDF reports. How can I use regular expression in Qweb report to change the output?

I want to create a bold text string from * * a bold text string * *

For that I use

Bacon Burger

in my template. In my model (wich I inherit from sale.order) I define a method 

def minimarkupmagic(self,txt):
	​txt = re.sub(r'\*{2,2}(.*?)\*{2,2}', r'\1', txt)
	​txt = re.sub(r'_{2,2}(.*?)_{2,2}', r'\1', txt)
	​txtArr = txt.split('\n')
	​txt = '
'.join(txtArr)
	​return txt

and send it to my template within 

docargs = {
	...,
	​'minimarkupmagic': self.minimarkupmagic
}

from def render_html().

It works half way: I only get an output like

in my report, so it seems that the method runs after the rendering of the HTML to PDF.

So how could I get my HTML get interpreted earlier and get my correct output?

Thnx!

EDIT: I just found the answer: I found out that it works if you use t-raw. I used t-esc... :-)