--- ../.venv/lib/python3.6/site-packages/charmhelpers/contrib/network/ip.py.orig        2020-10-02 21:36:12.654080192 +0000
+++ ../.venv/lib/python3.6/site-packages/charmhelpers/contrib/network/ip.py     2020-10-02 21:36:24.110214789 +0000
@@ -230,7 +230,8 @@
     configured network interfaces
     '''
     netmask = get_netmask_for_address(ip_address)
-    return str(netaddr.IPNetwork("%s/%s" % (ip_address, netmask)).cidr)
+    if netmask != None:
+        return str(netaddr.IPNetwork("%s/%s" % (ip_address, netmask)).cidr)


 def format_ipv6_addr(address):