find /usr/include -path '*gnutls/gnutls.h' | egrep --max-count=1 . \
|| fatal "No gnutls/gnutls.h. Try: apt-get install libgnutls28-dev"
echo -n 'virtualenv: '
- python3 -m venv -h | egrep --max-count=1 . \
+ python3 -m venv --help | grep -q '^usage: venv ' \
+ && echo "venv module found" \
|| fatal "No virtualenv. Try: apt-get install python3-venv"
echo -n 'Python3 pyconfig.h: '
find /usr/include -path '*/python3*/pyconfig.h' | egrep --max-count=1 . \