[2145] explicitly imported isc.log.

src/lib/python/isc/datasrc/tests/zone_loader_test.py

@@ -13,6 +13,7 @@
 # NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
 # WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 
+import isc.log
 import isc.datasrc
 import isc.dns