message: Use `venv` if `virtualenv` is not available.
diff: @@ -415,6 +415,7 @@ create_activate_virtualenv() {
  # to create the virtualenv directory for testing. Use the -p flag to specify
  # the python version inside the to-be-created virtualenv directory.
  ${PYTHON_BIN_PATH_INIT} -m virtualenv -p ${PYTHON_BIN_PATH_INIT} ${VIRTUALENV_FLAGS} ${VIRTUALENV_DIR} || \
  + ${PYTHON_BIN_PATH_INIT} -m venv ${VIRTUALENV_DIR} || \
  die "FAILED: Unable to create virtualenv"
  source "${VIRTUALENV_DIR}/bin/activate" || \
  