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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def unload_plugins(self, ):
 """ Unloads all loaded plugins :returns: None :rtype: None :raises: None """

        for p in self.__plugins.values():
            if p.is_loaded():
                try:
                    p._unload()
                    log.info('Uninitialized the plugin: %s' % p)
                except errors.PluginUninitError:
                    log.error('Uninitialization of the plugin: %s failed.' % p)