[mod] remove unused import

use
from searx.engines.duckduckgo import _fetch_supported_languages, supported_languages_url  # NOQA
so it is possible to easily remove all unused import using autoflake:
autoflake --in-place --recursive --remove-all-unused-imports searx tests

searx/engines/duden.py

@@ -60,7 +60,6 @@ def response(resp):
 
     except:
         logger.debug("Couldn't read number of results.")
-        pass
 
     for result in eval_xpath(dom, '//section[not(contains(@class, "essay"))]'):
         try: