Binary package “python3-venv” in ubuntu xenial

pyvenv-3 binary for python3 (default python3 version)

 Python, the high-level, interactive object oriented language,
 includes an extensive class library with lots of goodies for
 network programming, system administration, sounds and graphics.
 .
 This package is a dependency package, which depends on Debian's default
 Python 3 version (currently v3.5).