python: make dbus, gi examples, and debug-helper.py python3 ready

https://bugzilla.gnome.org/show_bug.cgi?id=791121

examples/python/dbus/update-secrets.py

@@ -37,16 +37,16 @@ def change_secrets_in_one_setting(proxy, config, setting_name):
         # returns a dict of dicts mapping name::setting, where setting is a dict
         # mapping key::value.  Each member of the 'setting' dict is a secret
         secrets = proxy.GetSecrets(setting_name)
-        print "Current secrets:", secrets
+        print("Current secrets:" + secrets)
 
         # Ask user for new secrets and put them into our connection config
         for setting in secrets:
             for key in secrets[setting]:
                 new_secret = raw_input ("Enter new secret for '%s' in '%s': " % (key, setting))
                 config[setting_name][key] = new_secret
-    except Exception, e:
+    except Exception as e:
         #code = str(e).split(':')[0]
-        #print "Exception:", str(e)
+        #print("Exception:" + str(e))
         pass
 
 def change_secrets(con_path, config):
@@ -76,7 +76,7 @@ def find_connection(name):
         connection = dbus.Interface(con_proxy, "org.freedesktop.NetworkManager.Settings.Connection")
         try:
             config = connection.GetSettings()
-        except Exception, e:
+        except Exception as e:
             pass
 
         # Find connection by the id
@@ -101,7 +101,7 @@ if len(sys.argv) != 2:
 # Find the connection
 con = find_connection(sys.argv[1])
 
-print "Connection found: ", con_path
+print("Connection found: " + con_path)
 
 if con:
     # Obtain new secrets and put then into connection dict