From 8a54f927f6f440219393ba1c9532eb91b881778a Mon Sep 17 00:00:00 2001
From: Junzi Sun <junzisun@gmail.com>
Date: Thu, 19 Apr 2018 09:45:56 +0200
Subject: [PATCH] fix deprecation warning

---
 pyModeS/decoder/ehs.py | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/pyModeS/decoder/ehs.py b/pyModeS/decoder/ehs.py
index ad1570b..05451d2 100644
--- a/pyModeS/decoder/ehs.py
+++ b/pyModeS/decoder/ehs.py
@@ -1,14 +1,14 @@
 from __future__ import absolute_import, print_function, division
+import warnings
+warnings.simplefilter('once', DeprecationWarning)
 
 from pyModeS.decoder.bds.bds40 import *
 from pyModeS.decoder.bds.bds50 import *
 from pyModeS.decoder.bds.bds60 import *
+from pyModeS.decoder.bds import infer
 
 def BDS(msg):
-    import warnings
-    from pyModeS.decoder.bds import infer
-    warnings.simplefilter('always', DeprecationWarning)
-    warnings.warn("pms.ehs.BDS() is deprecated, use pms.bds.infer() instead", DeprecationWarning)
+    warnings.warn("pms.ehs.BDS() is deprecated, use pms.bds.infer() instead.", DeprecationWarning)
     return infer(msg)
 
 def icao(msg):