def getThemeIds(self):
     if self._themeids:
         return self._themeids
     providers = self.getThemesProviders()
     themeids = []
     for provider in providers:
         themeids.extend(provider.getThemeIds())
     self._themeids = list(set(themeids))
     return self._themeids
 def getThemeById(self,id):
     providers = self.getThemesProviders()
     for provider in providers:
         if id in provider.getThemeIds():
             return provider.getThemeById(id)