PROTON-2319 Remove Python 2.3 and Jython 2.5 compatibility code (#288)

diff --git a/python/tests/proton_tests/engine.py b/python/tests/proton_tests/engine.py
index 2cf41c6..586f974 100644
--- a/python/tests/proton_tests/engine.py
+++ b/python/tests/proton_tests/engine.py
@@ -39,18 +39,6 @@
 #  + resuming
 #    - locally and remotely created deliveries with the same tag
 
-# Jython 2.5 needs this:
-try:
-    bytes()
-except:
-    bytes = str
-
-# and this...
-try:
-    bytearray()
-except:
-    def bytearray(x):
-        return b'\x00' * x
 
 OUTPUT_SIZE = 10 * 1024
 
diff --git a/tools/python/mllib/__init__.py b/tools/python/mllib/__init__.py
index c60657d..e520d61 100644
--- a/tools/python/mllib/__init__.py
+++ b/tools/python/mllib/__init__.py
@@ -71,17 +71,12 @@
 
 
 def xml_parse(filename, path=()):
-    if sys.version_info[0:2] == (2, 3):
-        # XXX: this is for older versions of python
-        source = "file://%s" % os.path.abspath(filename)
-    else:
-        source = filename
     h = parsers.XMLParser()
     p = xml.sax.make_parser()
     p.setContentHandler(h)
     p.setErrorHandler(ErrorHandler())
     p.setEntityResolver(Resolver(path))
-    p.parse(source)
+    p.parse(filename)
     return h.parser.tree