Index: Lib/distutils/command/upload.py
===================================================================
--- Lib/distutils/command/upload.py	(revision 67045)
+++ Lib/distutils/command/upload.py	(working copy)
@@ -7,11 +7,11 @@
 from distutils.spawn import spawn
 from distutils import log
 from hashlib import md5
-import os
+import os, io
 import socket
 import platform
 import configparser
-import http.client
+import http.client as httpclient
 import base64
 import urllib.parse
 
@@ -113,33 +113,35 @@
                                      open(filename+".asc").read())
 
         # set up the authentication
-        auth = "Basic " + base64.encodestring(self.username + ":" + self.password).strip()
+        user_pass = (self.username + ":" + self.password).encode('ascii')
+        # The exact encoding of the authentication string is debated.
+        # Anyway PyPI only accepts ascii for both username or password.
+        auth = "Basic " + base64.encodestring(user_pass).strip().decode('ascii')
 
         # Build up the MIME payload for the POST data
         boundary = '--------------GHSKFJDLGDS7543FJKLFHRE75642756743254'
-        sep_boundary = '\n--' + boundary
-        end_boundary = sep_boundary + '--'
-        body = io.StringIO()
+        sep_boundary = b'\n--' + boundary.encode('ascii')
+        end_boundary = sep_boundary + b'--'
+        body = io.BytesIO()
         for key, value in data.items():
+            title = '\nContent-Disposition: form-data; name="%s"' % key
             # handle multiple entries for the same name
             if type(value) != type([]):
                 value = [value]
             for value in value:
                 if type(value) is tuple:
-                    fn = ';filename="%s"' % value[0]
+                    title += '; filename="%s"' % value[0]
                     value = value[1]
                 else:
-                    fn = ""
-                value = str(value)
+                    value = str(value).encode('utf-8')
                 body.write(sep_boundary)
-                body.write('\nContent-Disposition: form-data; name="%s"'%key)
-                body.write(fn)
-                body.write("\n\n")
+                body.write(title.encode('utf-8'))
+                body.write(b"\n\n")
                 body.write(value)
-                if value and value[-1] == '\r':
-                    body.write('\n')  # write an extra newline (lurve Macs)
+                if value and value[-1:] == b'\r':
+                    body.write(b'\n')  # write an extra newline (lurve Macs)
         body.write(end_boundary)
-        body.write("\n")
+        body.write(b"\n")
         body = body.getvalue()
 
         self.announce("Submitting %s to %s" % (filename, self.repository), log.INFO)
@@ -152,9 +154,9 @@
             urllib.parse.urlparse(self.repository)
         assert not params and not query and not fragments
         if schema == 'http':
-            http = http.client.HTTPConnection(netloc)
+            http = httpclient.HTTPConnection(netloc)
         elif schema == 'https':
-            http = http.client.HTTPSConnection(netloc)
+            http = httpclient.HTTPSConnection(netloc)
         else:
             raise AssertionError("unsupported schema "+schema)