On Debian Jessie, apt-get will install Python3.4. To install Python 3.6 from source and create a virtual environment is trivial.


wget https://www.python.org/ftp/python/3.6.0/Python-3.6.0.tgz
tar xvf Python-3.6.0.tgz
cd Python-3.6.0
./configure --enable-optimizations
make -j8
sudo make altinstall


Then, to create a python3.6 virtual environment


python3.6 -m venv my_env
source my_env/bin/activate
python --version # 3.6.0!