docs: def getKeyForAPI(cls, siteStore, apiName):
          """
          Get the API key for the named API, if one exists.
  
          @param siteStore: The site store.
          @type siteStore: L{axiom.store.Store}
  
          @param apiName: The name of the API.
          @type apiName: C{unicode} (L{APIKey} constant)
  
          @rtype: L{APIKey} or C{NoneType}
          """
          return siteStore.findUnique(
              cls, cls.apiName == apiName, default=None)