utils: Add time_logger context manager

mopidy/utils/timer.py

@@ -0,0 +1,16 @@
+from __future__ import unicode_literals
+
+import contextlib
+import logging
+import time
+
+
+logger = logging.getLogger(__name__)
+TRACE = logging.getLevelName('TRACE')
+
+
+@contextlib.contextmanager
+def time_logger(name, level=TRACE):
+    start = time.time()
+    yield
+    logger.log(level, '%s took %dms', name, (time.time() - start) * 1000)