Sbuild errors on python install

["L. van Belle" <belle@samba.org>]

Good day Everybody..

Im prepaing a system to build /rebuild packages with sbuild. 

I used this to setup : 
https://wiki.debian.org/sbuild 
( its missing a few packages like : dh-python dh-make ) 

It works but.. (which is why i sending this email). 

Per example, im updating Talloc to 2.3.3
Running : sbuild -d bullseye  works fine.
All my amd64 packages are created, no errors, perfect.. Just.. 

When I run the builder with : sbuild -d bullseye --host=armhf 
So i can cross-build the armhf packages. 

Im hitting this error and i cant find why or find any solution. 

Setting up python3.9-minimal:armhf (3.9.2-1) ...
/var/lib/dpkg/info/python3.9-minimal.postinst: 51: /usr/bin/python3.9: Exec
format error
dpkg: error processing package python3.9-minimal:armhf (--configure):
 installed python3.9-minimal:armhf package post-installation script
subprocess returned error exit status 126
Setting up liblocale-gettext-perl (1.07-4+b1) ...

What am i missing? Anyone? Please? Im stuck.. 
Or should i report this as bug? 
I dont know/cant find if this is a config thingy or bug thingy.. ;-) 

Best regards, 

Louis