Modernize code for easier Python 3 port

- Replace print statement with function call
- Replace except ..., ...: syntax with except ... as ...:
- Simplify obsolete try ... except ... code block
- Replace some unicode calls with u-prefixed strings
- Do not use `len(SEQUENCE)` to determine if a sequence is empty
- Replace dictionary creation
- Drop support for GObject static bindings

whipper/extern/task/task.py

@@ -22,10 +22,7 @@ from __future__ import print_function
 import logging
 import sys
 
-try:
-    from gi.repository import GLib as gobject
-except ImportError:
-    import gobject
+from gi.repository import GLib as GLib
 
 logger = logging.getLogger(__name__)
 
@@ -463,7 +460,7 @@ class TaskRunner(LogStub):
 
 class SyncRunner(TaskRunner, ITaskListener):
     """
-    I run the task synchronously in a gobject MainLoop.
+    I run the task synchronously in a GObject MainLoop.
     """
 
     def __init__(self, verbose=True):
@@ -478,11 +475,11 @@ class SyncRunner(TaskRunner, ITaskListener):
             self._verboseRun = verbose
         self._skip = skip
 
-        self._loop = gobject.MainLoop()
+        self._loop = GLib.MainLoop()
         self._task.addListener(self)
         # only start the task after going into the mainloop,
         # otherwise the task might complete before we are in it
-        gobject.timeout_add(0L, self._startWrap, self._task)
+        GLib.timeout_add(0L, self._startWrap, self._task)
         self.debug('run loop')
         self._loop.run()
 
@@ -526,7 +523,7 @@ class SyncRunner(TaskRunner, ITaskListener):
         self.debug('schedule: scheduling %r(*args=%r, **kwargs=%r)',
                    callable, args, kwargs)
 
-        gobject.timeout_add(int(delta * 1000L), c)
+        GLib.timeout_add(int(delta * 1000L), c)
 
     # ITaskListener methods
     def progressed(self, task, value):