diff --git a/scripts/build/verinfo.py b/scripts/build/verinfo.py
index f89956d1a53..4ff069450b6 100644
--- a/scripts/build/verinfo.py
+++ b/scripts/build/verinfo.py
@@ -5,6 +5,7 @@
 
 from __future__ import with_statement
 
+import io
 import re
 import sys
 
@@ -63,7 +64,7 @@ def extract_version(input):
 build, outfmt, srcfile, dstfile = parse_args()
 
 try:
-    fp = open(srcfile, 'rU')
+    fp = io.open(srcfile, 'r')
 except IOError:
     sys.stderr.write("Unable to open source file '%s'\n" % srcfile)
     sys.exit(1)
diff --git a/src/devices/cpu/m6502/m6502make.py b/src/devices/cpu/m6502/m6502make.py
index 31f10d4f8d1..422b5a8ab74 100755
--- a/src/devices/cpu/m6502/m6502make.py
+++ b/src/devices/cpu/m6502/m6502make.py
@@ -4,13 +4,14 @@
 
 from __future__ import print_function
 
+import io
+import logging
+import sys
+
 USAGE = """
 Usage:
 %s prefix {opc.lst|-} disp.lst device.inc deviced.inc
 """
-import sys
-import logging
-
 MAX_STATES = 0
 
 def load_opcodes(fname):
@@ -18,7 +19,7 @@ def load_opcodes(fname):
     opcodes = []
     logging.info("load_opcodes: %s", fname)
     try:
-        f = open(fname, "rU")
+        f = io.open(fname, "r")
     except Exception:
         err = sys.exc_info()[1]
         logging.error("cannot read opcodes file %s [%s]", fname, err)
@@ -41,7 +42,7 @@ def load_disp(fname):
     logging.info("load_disp: %s", fname)
     states = []
     try:
-        f = open(fname, "rU")
+        f = io.open(fname, "r")
     except Exception:
         err = sys.exc_info()[1]
         logging.error("cannot read display file %s [%s]", fname, err)
diff --git a/src/devices/cpu/m6809/m6809make.py b/src/devices/cpu/m6809/m6809make.py
index 8838b960191..1f505d22197 100644
--- a/src/devices/cpu/m6809/m6809make.py
+++ b/src/devices/cpu/m6809/m6809make.py
@@ -2,8 +2,9 @@
 # license:BSD-3-Clause
 # copyright-holders:Olivier Galibert
 
-import sys
+import io
 import re
+import sys
 
 # Initial state
 state = 1
@@ -16,7 +17,7 @@ def load_file(fname, lines):
 	if path != "":
 		path += '/'
 	try:
-		f = open(fname, "rU")
+		f = io.open(fname, "r")
 	except Exception:
 		err = sys.exc_info()[1]
 		sys.stderr.write("Cannot read opcodes file %s [%s]\n" % (fname, err))
diff --git a/src/devices/cpu/mcs96/mcs96make.py b/src/devices/cpu/mcs96/mcs96make.py
index 2a9398cd662..7a7f4a470d8 100644
--- a/src/devices/cpu/mcs96/mcs96make.py
+++ b/src/devices/cpu/mcs96/mcs96make.py
@@ -4,12 +4,13 @@
 
 from __future__ import print_function
 
+import io
+import sys
+
 USAGE = """
 Usage:
 %s mcs96ops.lst mcs96.inc
 """
-import sys
-
 def save_full_one(f, t, name, source):
     print("void %s_device::%s_full()" % (t, name), file=f)
     print("{", file=f)
@@ -73,7 +74,7 @@ class OpcodeList:
         self.ea = {}
         self.macros = {}
         try:
-            f = open(fname, "rU")
+            f = io.open(fname, "r")
         except Exception:
             err = sys.exc_info()[1]
             sys.stderr.write("Cannot read opcodes file %s [%s]\n" % (fname, err))
diff --git a/src/devices/cpu/tms57002/tmsmake.py b/src/devices/cpu/tms57002/tmsmake.py
index 326c07776da..cfda965d4ad 100755
--- a/src/devices/cpu/tms57002/tmsmake.py
+++ b/src/devices/cpu/tms57002/tmsmake.py
@@ -4,8 +4,9 @@
 
 from __future__ import print_function
 
-import sys
+import io
 import re
+import sys
 
 
 DASM_ARGS = {
@@ -323,7 +324,7 @@ class Instruction:
 def LoadLst(filename):
     instructions = []
     ins = None
-    for n, line in enumerate(open(filename, "rU")):
+    for n, line in enumerate(io.open(filename, "r")):
         line = line.rstrip()
         if not line and ins:
             # new lines separate intructions