There you see the requirements. You need to install those first. If some are not available from a repository, you can compile them manually. Done that, it should work.
So it seems like this should work:
sudo apt install -y libgtk-3-dev gettext ffmpeg python-pip
pip2 install -U \
-f https://extras.wxpython.org/wxPython4/extras/linux/gtk3/ubuntu-16.04 \
wxPython
pip2 install twodict