You need Python 3.3 or higher, pip3 and git.
Let's clone the git repo to ~/udapi-python/, install dependencies
and setup $PATH and $PYTHONPATH accordingly:
cd
git clone https://github.com/udapi/udapi-python.git
pip3 install --user -r udapi-python/requirements.txt
echo '## Use Udapi from ~/udapi-python/ ##' >> ~/.bashrc
echo 'export PATH="$HOME/udapi-python/bin:$PATH"' >> ~/.bashrc
echo 'export PYTHONPATH="$HOME/udapi-python/:$PYTHONPATH"' >> ~/.bashrc
source ~/.bashrc # or open new bash