From Fedora:
python3 - recent HP release removed encoding/decoding to utf-8 in fax/pmlfax.py -
that results in text string going into translate function in base/utils.py, which
expects binary string because of parameters. Remove this patch if base/utils.py
code gets fixed.

Index: fax/pmlfax.py
--- fax/pmlfax.py.orig
+++ fax/pmlfax.py
@@ -145,8 +145,8 @@ class PMLFaxDevice(FaxDevice):
 
     def getPhoneNum(self):
         if PY3:
-            data = utils.printable(self.getPML(pml.OID_FAX_LOCAL_PHONE_NUM)[1])
-            return data
+            data = utils.printable(self.getPML(pml.OID_FAX_LOCAL_PHONE_NUM)[1].encode('utf-8'))
+            return data.decode('utf-8')
         else:
             return utils.printable(self.getPML(pml.OID_FAX_LOCAL_PHONE_NUM)[1])
     phone_num = property(getPhoneNum, setPhoneNum, doc="OID_FAX_LOCAL_PHONE_NUM")
@@ -157,8 +157,8 @@ class PMLFaxDevice(FaxDevice):
 
     def getStationName(self):
         if PY3:
-            data = utils.printable(self.getPML(pml.OID_FAX_STATION_NAME)[1])
-            return data
+            data = utils.printable(self.getPML(pml.OID_FAX_STATION_NAME)[1].encode('utf-8'))
+            return data.decode('utf-8')
         else:
             return utils.printable(self.getPML(pml.OID_FAX_STATION_NAME)[1])