Update Pyhon3.ipynb

Pyhon3.ipynb

@@ -15,7 +15,7 @@
     "  - Zope5 on python3.9 seems a little bit faster than Zope4 on python2\n",
     "  - Zope5 on python3.9 seems to handle the load in this test ( no crash etc )\n",
     "  - zodbupdate patch does not seem to add a significant overhead here, but this test writes more that it reads and the patch affect loading time\n",
-    "  - python3 seems to use more memory\n",
+    "  - python3 seems to use less memory\n",
     "  - ZODB files seems slightly larger (this was not investigated)\n",
     "  - results from this test are a bit hard to read and not really scientific, the result on py2 is from a few months ago\n"
    ]