diff --git a/spyderlib/plugins/__init__.py b/spyderlib/plugins/__init__.py
index <HASH>..<HASH> 100644
--- a/spyderlib/plugins/__init__.py
+++ b/spyderlib/plugins/__init__.py
@@ -20,7 +20,7 @@ These plugins inherit the following classes
 

 from spyderlib.qt.QtGui import (QDockWidget, QWidget, QShortcut, QCursor,

                                 QKeySequence, QMainWindow, QApplication)

-from spyderlib.qt.QtCore import SIGNAL, Qt, QObject, Signal, Slot

+from spyderlib.qt.QtCore import SIGNAL, Qt, QObject, Signal

 

 import sys

 

@@ -204,7 +204,7 @@ class SpyderPluginMixin(object):
         Use a SIGNAL to call it, e.g.:

         plugin.sig_option_changed.emit('show_all', checked)

         """

-        CONF.set(self.CONF_SECTION, option, value)

+        CONF.set(self.CONF_SECTION, str(option), value)

 

     def get_option(self, option, default=NoDefault):

         """Get a plugin option from configuration file"""
Spyder plugin mixin/widget - bugfix: signal 'sig_option_changed' was not working due to missing type conversion (PyQt API #1 only)