[compat] Replace deficient ChainMap class in Py3.3 and earlier

* fix version check

diff --git a/youtube_dl/compat.py b/youtube_dl/compat.py
index 366a93924a8ab4786929ded0d0aef591af91ec88..eca6d63de7264ed6a1373ccbb30a1e777c524db6 100644 (file)
--- a/youtube_dl/compat.py
+++ b/youtube_dl/compat.py
@@ -3005,7 +3005,7 @@ except ImportError:
 try:
     from collections import ChainMap as compat_collections_chain_map
     # Py3.3's ChainMap is deficient
-    if sys.version_info <= (3, 3):
+    if sys.version_info < (3, 4):
         raise ImportError
 except ImportError:
     # Py <= 3.3