DaVinci Resolve Python 3.6 not found
Based on strace is seems that fuscript binary searches for libpython2.7.so and libpython3.6.so
$ /opt/resolve/libs/Fusion/fuscript -l py3

DaVinci Resolve Script Interpreter
Copyright (C) 2005 - 2020 Blackmagic Design Pty. Ltd.

ERROR: Language 'py3' is not available.


E.g. on Debian based systems this could be installed, if you're lucky and the exact version is available for your distribution.
sudo apt install libpython3.6

The binary looks into several paths one of them is /usr/local/lib/libpython3.6.so. According to documentation this could be configured by PYTHONPATH env variable. However it doesn't seem to have any effect.
Using pyenv any Python version can be installed (we need shared libraries - *.so files):
env PYTHON_CONFIGURE_OPTS=&quot;--enable-shared&quot; pyenv install 3.6.11

then create a symlink:
sudo ln -s $HOME/.pyenv/versions/3.6.11/lib/python3.6 /usr/local/lib/python3.6
sudo ln -s $HOME/.pyenv/versions/3.6.11/lib/libpython3.so /usr/local/lib/libpython3.6.so

Finally console should be working (Resolve will need a restart):
$ /opt/resolve/libs/Fusion/fuscript -l py3 -i

DaVinci Resolve Script Interpreter
Copyright (C) 2005 - 2020 Blackmagic Design Pty. Ltd.

Cannot read termcap database;
using dumb terminal settings.
Py3&gt;