pmfg: destroy fetchgroup only if it exists

[Marko Myllynen <myllynen@xxxxxxxxxx>]

From: Frank Ch. Eigler <fche@xxxxxxxxxx>

---
 src/python/pcp/pmapi.py | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/python/pcp/pmapi.py b/src/python/pcp/pmapi.py
index e696330..8d0a786 100644
--- a/src/python/pcp/pmapi.py
+++ b/src/python/pcp/pmapi.py
@@ -2315,8 +2315,7 @@ class fetchgroup(object):
     def __del__(self):
         """Destroy the fetchgroup.  Drop references to fetchgroup_* items."""
 
-        assert self.pmfg.value != None
-        if LIBPCP != None: # might be called late during python3 shutdown; 
moot then
+        if LIBPCP != None and self.pmfg.value != None:
             sts = LIBPCP.pmDestroyFetchGroup(self.pmfg)
             if sts < 0:
                 raise pmErr(sts)

Thanks,

-- 
Marko Myllynen