docs: def activated(self, include_extras=True, extra_dists=[]):
          """A context manager which activates the virtualenv.
  
          :param list extra_dists: Paths added to the context after the virtualenv is activated.
  
          This context manager sets the following environment variables:
              * `PYTHONUSERBASE`
              * `VIRTUAL_ENV`
              * `PYTHONIOENCODING`
              * `PYTHONDONTWRITEBYTECODE`
  
          In addition, it activates the virtualenv inline by calling `activate_this.py`.
          """
  
          original_path = sys.path
          original_prefix = sys.prefix
          original_user_base = os.environ.get("PYTHONUSERBASE", None)
          original_venv = os.environ.get("VIRTUAL_ENV", None)
          parent_path = vistir.compat.Path(__file__).absolute().parent.parent.as_posix()
          prefix = self.prefix.as_posix()
          with vistir.contextmanagers.temp_environ(), vistir.contextmanagers.temp_path():
              os.environ["PATH"] = os.pathsep.join([
                  vistir.compat.fs_str(self.scripts_dir),
                  vistir.compat.fs_str(self.prefix.as_posix()),
                  os.environ.get("PATH", "")
              ])
              os.environ["PYTHONIOENCODING"] = vistir.compat.fs_str("utf-8")
              os.environ["PYTHONDONTWRITEBYTECODE"] = vistir.compat.fs_str("1")
              os.environ["PATH"] = self.base_paths["PATH"]
              os.environ["PYTHONPATH"] = self.base_paths["PYTHONPATH"]
              if self.is_venv:
                  os.environ["VIRTUAL_ENV"] = vistir.compat.fs_str(prefix)
              sys.path = self.sys_path
              sys.prefix = self.sys_prefix
              site.addsitedir(self.base_paths["purelib"])
              if include_extras:
                  site.addsitedir(parent_path)
                  extra_dists = list(self.extra_dists) + extra_dists
                  for extra_dist in extra_dists:
                      if extra_dist not in self.get_working_set():
                          extra_dist.activate(self.sys_path)
                  sys.modules["recursive_monkey_patch"] = self.recursive_monkey_patch
              try:
                  yield
              finally:
                  del os.environ["VIRTUAL_ENV"]
                  if original_user_base:
                      os.environ["PYTHONUSERBASE"] = original_user_base
                  if original_venv:
                      os.environ["VIRTUAL_ENV"] = original_venv
                  sys.path = original_path
                  sys.prefix = original_prefix
                  six.moves.reload_module(pkg_resources)