2to3: Apply `imports` fixer.

The `imports` fixer deals with the standard packages that have been
renamed, removed, or methods that have moved.

cPickle      -- removed, use pickle
commands     -- removed, getoutput, getstatusoutput moved to subprocess
urlparse     -- removed, urlparse moved to urllib.parse
cStringIO    -- removed, use StringIO or io.StringIO
copy_reg     -- renamed copyreg
_winreg      -- renamed winreg
ConfigParser -- renamed configparser
__builtin__  -- renamed builtins

In the case of `cPickle`, it is imported as `pickle` when python < 3 and
performance may be a consideration, but otherwise plain old `pickle` is
used.

Dealing with `StringIO` is a bit tricky. There is an `io.StringIO`
function in the `io` module, available since Python 2.6, but it expects
unicode whereas `StringIO.StringIO` expects ascii. The Python 3
equivalent is then `io.BytesIO`. What I have done here is used BytesIO
for anything that is emulating a file for testing purposes. That is more
explicit than using a redefined StringIO as was done before we dropped
support for Python 2.4 and 2.5.

Closes #3180.

2 files changed, 8 insertions, 3 deletions

diff --git a/tools/py3tool.py b/tools/py3tool.py
index 656327450..d7fc94240 100755
--- a/tools/py3tool.py
+++ b/tools/py3tool.py
@@ -77,7 +77,8 @@ FIXES_TO_SKIP = [
     'raw_input',
     'xreadlines',
     'xrange',
-    'import'
+    'import',
+    'imports'
 ]
 
 skip_fixes= []
diff --git a/tools/win32build/build.py b/tools/win32build/build.py
index 43d8a395d..dc12e807d 100644
--- a/tools/win32build/build.py
+++ b/tools/win32build/build.py
@@ -88,8 +88,12 @@ def move_binary(arch, pyver):
             os.path.join("binaries", get_binary_name(arch)))
 
 def get_numpy_version():
-    import __builtin__
-    __builtin__.__NUMPY_SETUP__ = True
+    if sys.version_info[0] >= 3:
+        import builtins
+    else:
+        import __builtin__ as builtins
+
+    builtins.__NUMPY_SETUP__ = True
     from numpy.version import version
     return version