diff --git a/tools/python/scripts/convert-legacy-stream b/tools/python/scripts/convert-legacy-stream
index 5f80f13654..b0d81aa92e 100755
--- a/tools/python/scripts/convert-legacy-stream
+++ b/tools/python/scripts/convert-legacy-stream
@@ -5,6 +5,8 @@
 Convert a legacy migration stream to a v2 stream.
 """
 
+from __future__ import print_function
+
 import sys
 import os, os.path
 import syslog
@@ -12,6 +14,7 @@ import traceback
 
 from struct import calcsize, unpack, pack
 
+from xen.util import open_file_or_fd as open_file_or_fd
 from xen.migration import legacy, public, libxc, libxl, xl
 
 __version__ = 1
@@ -39,16 +42,16 @@ def info(msg):
             for line in msg.split("\n"):
                 syslog.syslog(syslog.LOG_INFO, line)
         else:
-            print msg
+            print(msg)
 
 def err(msg):
     """Error message, routed to appropriate destination"""
     if log_to_syslog:
         for line in msg.split("\n"):
             syslog.syslog(syslog.LOG_ERR, line)
-    print >> sys.stderr, msg
+    print(msg, file = sys.stderr)
 
-class StreamError(StandardError):
+class StreamError(Exception):
     """Error with the incoming migration stream"""
     pass
 
@@ -70,7 +73,7 @@ class VM(object):
 
         # libxl
         self.libxl = fmt == "libxl"
-        self.emu_xenstore = "" # NUL terminated key&val pairs from "toolstack" records
+        self.emu_xenstore = b"" # NUL terminated key&val pairs from "toolstack" records
 
 def write_libxc_ihdr():
     stream_write(pack(libxc.IHDR_FORMAT,
@@ -336,7 +339,7 @@ def read_libxl_toolstack(vm, data):
         if twidth == 64:
             name = name[:-4]
 
-        if name[-1] != '\x00':
+        if name[-1] != b'\x00':
             raise StreamError("physmap name not NUL terminated")
 
         root = "physmap/%x" % (phys,)
@@ -347,7 +350,7 @@ def read_libxl_toolstack(vm, data):
         for key, val in zip(kv[0::2], kv[1::2]):
             info("    '%s' = '%s'" % (key, val))
 
-        vm.emu_xenstore += '\x00'.join(kv) + '\x00'
+        vm.emu_xenstore += b'\x00'.join(kv) + b'\x00'
 
 
 def read_chunks(vm):
@@ -534,7 +537,7 @@ def read_qemu(vm):
     sig, = unpack("21s", rawsig)
     info("Qemu signature: %s" % (sig, ))
 
-    if sig == "DeviceModelRecord0002":
+    if sig == b"DeviceModelRecord0002":
         rawsz = rdexact(4)
         sz, = unpack("I", rawsz)
         qdata = rdexact(sz)
@@ -617,36 +620,6 @@ def read_legacy_stream(vm):
         return 2
     return 0
 
-def open_file_or_fd(val, mode):
-    """
-    If 'val' looks like a decimal integer, open it as an fd.  If not, try to
-    open it as a regular file.
-    """
-
-    fd = -1
-    try:
-        # Does it look like an integer?
-        try:
-            fd = int(val, 10)
-        except ValueError:
-            pass
-
-        # Try to open it...
-        if fd != -1:
-            return os.fdopen(fd, mode, 0)
-        else:
-            return open(val, mode, 0)
-
-    except StandardError, e:
-        if fd != -1:
-            err("Unable to open fd %d: %s: %s" %
-                (fd, e.__class__.__name__, e))
-        else:
-            err("Unable to open file '%s': %s: %s" %
-                (val, e.__class__.__name__, e))
-
-    raise SystemExit(1)
-
 
 def main():
     from optparse import OptionParser
@@ -723,7 +696,7 @@ def main():
 if __name__ == "__main__":
     try:
         sys.exit(main())
-    except SystemExit, e:
+    except SystemExit as e:
         sys.exit(e.code)
     except KeyboardInterrupt:
         sys.exit(1)
diff --git a/tools/python/scripts/verify-stream-v2 b/tools/python/scripts/verify-stream-v2
index 3daf25791e..8355c2d206 100755
--- a/tools/python/scripts/verify-stream-v2
+++ b/tools/python/scripts/verify-stream-v2
@@ -3,12 +3,15 @@
 
 """ Verify a v2 format migration stream """
 
+from __future__ import print_function
+
 import sys
 import struct
 import os, os.path
 import syslog
 import traceback
 
+from xen.util import open_file_or_fd as open_file_or_fd
 from xen.migration.verify import StreamError, RecordError
 from xen.migration.libxc import VerifyLibxc
 from xen.migration.libxl import VerifyLibxl
@@ -25,7 +28,7 @@ def info(msg):
             for line in msg.split("\n"):
                 syslog.syslog(syslog.LOG_INFO, line)
         else:
-            print msg
+            print(msg)
 
 def err(msg):
     """Error message, routed to appropriate destination"""
@@ -33,7 +36,7 @@ def err(msg):
         if log_to_syslog:
             for line in msg.split("\n"):
                 syslog.syslog(syslog.LOG_ERR, line)
-        print >> sys.stderr, msg
+        print(msg, file = sys.stderr)
 
 def stream_read(_ = None):
     """Read from input"""
@@ -56,7 +59,7 @@ def skip_xl_header():
     """Skip over an xl header in the stream"""
 
     hdr = rdexact(32)
-    if hdr != "Xen saved domain, xl format\n \0 \r":
+    if hdr != b"Xen saved domain, xl format\n \0 \r":
         raise StreamError("No xl header")
 
     _, mflags, _, optlen = unpack_exact("=IIII")
@@ -86,7 +89,7 @@ def read_stream(fmt):
         err(traceback.format_exc())
         return 1
 
-    except StandardError:
+    except Exception:
         err("Script Error:")
         err(traceback.format_exc())
         err("Please fix me")
@@ -94,36 +97,6 @@ def read_stream(fmt):
 
     return 0
 
-def open_file_or_fd(val, mode, buffering):
-    """
-    If 'val' looks like a decimal integer, open it as an fd.  If not, try to
-    open it as a regular file.
-    """
-
-    fd = -1
-    try:
-        # Does it look like an integer?
-        try:
-            fd = int(val, 10)
-        except ValueError:
-            pass
-
-        # Try to open it...
-        if fd != -1:
-            return os.fdopen(fd, mode, buffering)
-        else:
-            return open(val, mode, buffering)
-
-    except StandardError, e:
-        if fd != -1:
-            err("Unable to open fd %d: %s: %s" %
-                (fd, e.__class__.__name__, e))
-        else:
-            err("Unable to open file '%s': %s: %s" %
-                (val, e.__class__.__name__, e))
-
-    raise SystemExit(2)
-
 def main():
     """ main """
     from optparse import OptionParser
@@ -168,7 +141,7 @@ def main():
 if __name__ == "__main__":
     try:
         sys.exit(main())
-    except SystemExit, e:
+    except SystemExit as e:
         sys.exit(e.code)
     except KeyboardInterrupt:
         sys.exit(2)
diff --git a/tools/python/xen/migration/libxc.py b/tools/python/xen/migration/libxc.py
index f24448a9ef..cbffd1975e 100644
--- a/tools/python/xen/migration/libxc.py
+++ b/tools/python/xen/migration/libxc.py
@@ -223,7 +223,7 @@ def verify_record(self):
             self.squashed_pagedata_records += 1
 
         padding = content[length:]
-        if padding != "\x00" * len(padding):
+        if padding != b"\x00" * len(padding):
             raise StreamError("Padding containing non0 bytes found")
 
         if rtype not in record_verifiers:
diff --git a/tools/python/xen/migration/libxl.py b/tools/python/xen/migration/libxl.py
index d5f54dc489..79f4024e72 100644
--- a/tools/python/xen/migration/libxl.py
+++ b/tools/python/xen/migration/libxl.py
@@ -128,7 +128,7 @@ def verify_record(self):
         content = self.rdexact(contentsz)
 
         padding = content[length:]
-        if padding != "\x00" * len(padding):
+        if padding != b"\x00" * len(padding):
             raise StreamError("Padding containing non0 bytes found")
 
         if rtype not in record_verifiers:
diff --git a/tools/python/xen/migration/verify.py b/tools/python/xen/migration/verify.py
index 7a42dbfc58..1e38f4a3c0 100644
--- a/tools/python/xen/migration/verify.py
+++ b/tools/python/xen/migration/verify.py
@@ -7,11 +7,11 @@
 
 from struct import calcsize, unpack
 
-class StreamError(StandardError):
+class StreamError(Exception):
     """Error with the stream"""
     pass
 
-class RecordError(StandardError):
+class RecordError(Exception):
     """Error with a record in the stream"""
     pass
 
diff --git a/tools/python/xen/util.py b/tools/python/xen/util.py
new file mode 100644
index 0000000000..a11358eefa
--- /dev/null
+++ b/tools/python/xen/util.py
@@ -0,0 +1,23 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+import os
+
+def open_file_or_fd(val, *argl, **kwargs):
+    """
+    If 'val' looks like a decimal integer, open it as an fd.  If not, try to
+    open it as a regular file.
+    """
+
+    fd = -1
+    try:
+        # Does it look like an integer?
+        fd = int(val, 10)
+    except ValueError:
+        pass
+
+    # Try to open it...
+    if fd != -1:
+        return os.fdopen(fd, *argl, **kwargs)
+    else:
+        return open(val, *argl, **kwargs)
