BLD: ci/print_versions.py, LC_ALL/LANG should default to None

Author: y-p

ci/print_versions.py

@@ -8,8 +8,8 @@
     import os
     (sysname, nodename, release, version, machine) = os.uname()
     print("OS: %s %s %s %s" % (sysname, release, version,machine))
-    print("LC_ALL: %s" % os.environ['LC_ALL'])
-    print("LANG: %s" % os.environ['LANG'])
+    print("LC_ALL: %s" % os.environ.get('LC_ALL',"None"))
+    print("LANG: %s" % os.environ.get('LANG',"None"))
 except:
     pass