Clicking help button in Desktop Notifications crashes app

backtrace:
:DesktopNotification.py:211:onBtnHelp:AttributeError: 'module' object has no attribute 'help'
:
:Traceback (most recent call last):
: File "/usr/share/decibel-audio-player/src/modules/DesktopNotification.py", line 211, in onBtnHelp
: helpDlg = gui.help.HelpDlg(MOD_INFO[modules.MODINFO_L10N])
:AttributeError: 'module' object has no attribute 'help'
:
:Local variables in innermost frame:
:media: <module 'media' from '/usr/share/decibel-audio-player/src/media/__init__.pyc'>
:gui: <module 'gui' from '/usr/share/decibel-audio-player/src/gui/__init__.pyc'>
:btn: <gtk.Button object at 0x17615f0 (GtkButton at 0xec5490)>
:self: <DesktopNotification.DesktopNotification instance at 0x109ffc8>

comment:
:1. Go to preferences
:2. Desktop -> Desktop notification. Enable.
:3. Open settings (for desktop notif.)
:4. Click on Help

Fedora bug: https://bugzilla.redhat.com/show_bug.cgi?id=835917