fix lint errors2

archivebox/core/settings.py

@@ -71,7 +71,7 @@ AUTHENTICATION_BACKENDS = [
 DEBUG_TOOLBAR = False
 if DEBUG:
     try:
-        import debug_toolbar
+        import debug_toolbar   # noqa
         DEBUG_TOOLBAR = True
     except ImportError:
         pass

archivebox/index/schema.py

@@ -178,7 +178,6 @@ class Link:
             raise
     
     def _asdict(self, extended=False):
-        from core.models import Snapshot
         info = {
             'schema': 'Link',
             'url': self.url,