Как я могу выполнить lightread на Ubuntu 16.04?

Я пытался выполнить lightread, я пытался записать команду 'lightread', но это показывает мне это сообщение:

/home/quickly_trunk/lightread/__init__.py:40: PyGIWarning: Gtk was imported without specifying a version first. Use gi.require_version('Gtk', '3.0') before import to ensure that the right version gets loaded.
  from gi.repository import Gtk, Gio  # pylint: disable=E0611
/home/quickly_trunk/lightread/LightreadWindow.py:44: PyGIWarning: Notify was imported without specifying a version first. Use gi.require_version('Notify', '0.7') before import to ensure that the right version gets loaded.
  from gi.repository import Gtk, Gdk, WebKit, Notify, Soup  # pylint: disable=E0611
/home/quickly_trunk/lightread/LightreadWindow.py:44: PyGIWarning: Soup was imported without specifying a version first. Use gi.require_version('Soup', '2.4') before import to ensure that the right version gets loaded.
  from gi.repository import Gtk, Gdk, WebKit, Notify, Soup  # pylint: disable=E0611
Traceback (most recent call last):
  File "/home/quickly_trunk/bin/lightread", line 60, in <module>
    import lightread
  File "/home/lucifer/Downloads/quickly_trunk/lightread/__init__.py", line 42, in <module>
    from lightread import LightreadWindow
  File "/home/lucifer/Downloads/quickly_trunk/lightread/LightreadWindow.py", line 44, in <module>
    from gi.repository import Gtk, Gdk, WebKit, Notify, Soup  # pylint: disable=E0611
ImportError: cannot import name WebKit

Сегодня я просто загружаю Ubuntu, и я не знаю то, что продолжается.Спасибо.