python 2.7 - os.popen "function not implemented" / mount -o loop fails

[torpesco]

Is there a reason pflask doesn't use devtmpfs for /dev? To have a minimal set of devices available?

I tried to use pflask to build a project in an isolated chroot environment recently and ran into two issues:

1. os.popen in Python 2.7 fails. I get "[Errno 38] Function not implemented".
   • Using popen() in a test C program worked fine.
   • os.popen is deprecated. When I changed the script in my working copy to use subprocess.Popen, it worked.
2. mount -o loop fails

Both of these were fixed using this brute-force change:
torpesco@a40dfb0

Is there an alternate solution that would be preferred?