sized_controls.SizedDialog failing with no WS_EX_VALIDATE_RECURSIVELY

[ckhan]

Operating system: Windows 7 64-bit (also on MacOS Sierra)
wxPython version & source: 4.1.0a1.dev4130+927b6d94 from snapshot build
Python version & source: Python 2.7.13 (v2.7.13:a06454b1afa1, Dec 17 2016, 20:53:40) [MSC v.1500 64 bit (AMD64)] on win32

Description of the problem:

sized_controls.SizedDialog seems to be broken in latest builds:

#!/usr/bin/python

import wx
print wx.__version__

import wx.lib.sized_controls as sc

app = wx.App()
frame = wx.Frame(None, title='simple.py')
dlg = sc.SizedDialog(parent=frame, title="test dialog")
wx.StaticText(dlg.GetContentsPane(), label="a dialog")
frame.Show()
dlg.ShowModal()
app.MainLoop()

Returns this error:

Traceback (most recent call last):
  File "scdialog-broken-41.py", line 19, in <module>
    dlg = sc.SizedDialog(parent=frame, title="test dialog")
  File "u:/usr/extras/wx-4.1.0a1-win\wx\lib\sized_controls.py", line 600, in __init__
    self.SetExtraStyle(wx.WS_EX_VALIDATE_RECURSIVELY)
AttributeError: 'module' object has no attribute 'WS_EX_VALIDATE_RECURSIVELY'

[RobinD42]

This issue has been mentioned on Discuss wxPython. There might be relevant details there:

https://discuss.wxpython.org/t/wxpython-4-1-0-released/34564/1