Merge pull request #6571 from Carreau/jsonable

cast unicode to allow json dump

setupbase.py

@@ -579,7 +579,7 @@ def git_prebuild(pkg_dir, build_cmd=build_py):
             with open(out_pth, 'w') as out_file:
                 out_file.writelines([
                     '# GENERATED BY setup.py\n',
-                    'commit = "%s"\n' % repo_commit,
+                    'commit = u"%s"\n' % repo_commit,
                 ])
     return require_submodules(MyBuildPy)