'returns a dictionary of the configurable keybindings for a particular
extension,as they exist in the dictionary returned by GetCurrentKeySet;
that is, where previously used bindings are disabled.'

def GetExtensionKeys(self, extensionName):

    keysName = (extensionName + '_cfgBindings')
    activeKeys = self.GetCurrentKeySet()
    extKeys = {}
    if self.defaultCfg['extensions'].has_section(keysName):
        eventNames = self.defaultCfg['extensions'].GetOptionList(keysName)
        for eventName in eventNames:
            event = (('<<' + eventName) + '>>')
            binding = activeKeys[event]
            extKeys[event] = binding
    return extKeys
