diff --git a/Doc/tools/mkhowto b/Doc/tools/mkhowto
index 28f18b6..8826924 100755
--- a/Doc/tools/mkhowto
+++ b/Doc/tools/mkhowto
@@ -297,7 +297,7 @@
             # let the doctype-specific handler do some intermediate work:
             #
             self.run("%s %s" % (binary, self.doc))
-            self.latex_runs += 1
+            self.latex_runs = self.latex_runs + 1
             if os.path.isfile("mod%s.idx" % self.doc):
                 self.run("%s -s %s mod%s.idx"
                          % (MAKEINDEX_BINARY, ISTFILE, self.doc))
@@ -319,7 +319,7 @@
         if self.use_bibtex:
             self.run("%s %s" % (BIBTEX_BINARY, self.doc))
         self.run("%s %s" % (binary, self.doc))
-        self.latex_runs += 1
+        self.latex_runs = self.latex_runs + 1
 
     def process_synopsis_files(self):
         synopsis_files = glob.glob(self.doc + "*.syn")
diff --git a/Doc/tools/mkmodindex b/Doc/tools/mkmodindex
index 3bc4b95..b0211a7 100755
--- a/Doc/tools/mkmodindex
+++ b/Doc/tools/mkmodindex
@@ -117,9 +117,9 @@
     html = string.join(parts, '')
     program = os.path.basename(sys.argv[0])
     fp = options.get_output_file()
-    print >>fp, html.rstrip()
+    fp.write(string.rstrip(html) + "\n")
     if options.outputfile == "-":
-        print >>sys.stderr, "%s: %d index nodes" % (program, num_nodes)
+        sys.stderr.write("%s: %d index nodes\n" % (program, num_nodes))
     else:
         print
         print "%s: %d index nodes" % (program, num_nodes)
diff --git a/Doc/tools/support.py b/Doc/tools/support.py
index 86ecc6c..836adf4 100644
--- a/Doc/tools/support.py
+++ b/Doc/tools/support.py
@@ -8,6 +8,7 @@
 
 
 import getopt
+import string
 import sys
 
 
@@ -37,9 +38,9 @@
 
     def add_args(self, short=None, long=None):
         if short:
-            self.__short_args += short
+            self.__short_args = self.__short_args + short
         if long:
-            self.__long_args += long
+            self.__long_args = self.__long_args + long
 
     def parse(self, args):
         try:
@@ -49,10 +50,10 @@
             sys.stdout = sys.stderr
             self.usage()
             sys.exit(2)
-        self.args += args
+        self.args = self.args + args
         for opt, val in opts:
             if opt in ("-a", "--address"):
-                val = val.strip()
+                val = string.strip(val)
                 if val:
                     val = "<address>\n%s\n</address>\n" % val
                     self.variables["address"] = val