Remove unused imports

youtube_dl/extractor/dreisat.py

@@ -4,7 +4,6 @@ import re
 
 from .common import InfoExtractor
 from ..utils import (
-    determine_ext,
     unified_strdate,
 )
 

youtube_dl/extractor/mit.py

@@ -3,7 +3,6 @@ import json
 
 from .common import InfoExtractor
 from ..utils import (
-    compat_str,
     clean_html,
     get_element_by_id,
 )