Issue #6314: logging.basicConfig() performs extra checks on the "level" argument.

Lib/logging/__init__.py

@@ -1397,6 +1397,10 @@ def basicConfig(**kwargs):
         root.addHandler(hdlr)
         level = kwargs.get("level")
         if level is not None:
+            if str(level) == level: # If a string was passed, do more checks
+                if level not in _levelNames:
+                    raise ValueError("Unknown level: %r" % level)
+                level = _levelNames[level]
             root.setLevel(level)
 
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