Fix writing git commit ID to a file on build with Python 3.

setupbase.py

@@ -20,7 +20,6 b' from __future__ import print_function'
 #-------------------------------------------------------------------------------
 # Imports
 #-------------------------------------------------------------------------------
-import io
 import os
 import sys
 
@@ -55,11 +54,6 b' except NameError:'
         locs = locs or globs
         exec(compile(open(fname).read(), fname, "exec"), globs, locs)
 
-try:
-    unicode
-except NameError:
-    unicode = str
-
 # A little utility we'll need below, since glob() does NOT allow you to do
 # exclusion on multiple endings!
 def file_doesnt_endwith(test,endings):
@@ -396,9 +390,9 b' def record_commit_info(pkg_dir, build_cmd=build_py):'
             repo_commit = repo_commit.strip()
             # We write the installation commit even if it's empty
             out_pth = pjoin(self.build_lib, pkg_dir, 'utils', '_sysinfo.py')
-            with io.open(out_pth, 'w') as out_file:
-                out_file.writelines(map(unicode, [
+            with open(out_pth, 'w') as out_file:
+                out_file.writelines([
                     '# GENERATED BY setup.py\n',
-                    'commit = "%s"\n' % repo_commit,
-                ]))
+                    'commit = "%s"\n' % repo_commit.decode('ascii'),
+                ])
     return MyBuildPy