Merge pull request #616 from Dataliberate/master

Fix ImportError when __main__ already loaded

Author: joernhees

rdflib/__init__.py

@@ -73,10 +73,17 @@
 del sys
 
 import logging
-import __main__
-if not hasattr(__main__, '__file__'):
-    # show log messages in interactive mode
-    logging.basicConfig(level=logging.INFO)
+try:
+    import __main__
+    if not hasattr(__main__, '__file__'):
+        # show log messages in interactive mode
+        logging.basicConfig(level=logging.INFO)
+except ImportError:
+    #Main already imported from elsewhere
+    import warnings
+    warnings.warn('__main__ already imported', ImportWarning)
+    del warnings
+    
 logger = logging.getLogger(__name__)
 logger.info("RDFLib Version: %s" % __version__)