title: conflict between Spyder and wxPython?
body: <p>I am new in wxPython. Starting from a simple tutorial (http://wiki.wxpython.org/wxPython%20by%20Example), it seems that there is a conflict between Spyder and wxPython. 
  I can run the following script once (in the IPython console), using:</p>
  
  <pre><code>runfile(r'C:\Python27\Scripts\test\test.py')
  </code></pre>
  
  <p>which contains:</p>
  
  <pre><code>import wx
  
  class Frame(wx.Frame):
      def __init__(self, title):
          wx.Frame.__init__(self, None, title=title, size=(350,200))
  
  app = wx.App(redirect=True)
  top = Frame("Hello World")
  top.Show()
  app.MainLoop()
  </code></pre>
  
  <p>But the second time I run it, I got the following error:</p>
  
  <pre><code>Traceback (most recent call last):
    File "&lt;ipython console&gt;", line 1, in &lt;module&gt;
    File "C:\Python27\lib\site-packages\spyderlib\widgets\externalshell\sitecustomize.py", line 493, in runfile
  execfile(filename, namespace)
    File "C:\Python27\Scripts\test\test.py", line 14, in &lt;module&gt;
  top = Frame("Hello World")
    File "C:\Python27\Scripts\test\test.py", line 11, in __init__
  wx.Frame.__init__(self, None, title=title, size=(350,200))
    File "C:\Python27\lib\site-packages\wx-2.8-msw-unicode\wx\_windows.py", line 505, in __init__
  _windows_.Frame_swiginit(self,_windows_.new_Frame(*args, **kwargs))
  PyNoAppError: The wx.App object must be created first!
  </code></pre>
  
  <p>It do not really understand but apparently it is related to the fact that spyder is written using wxPython and a conflict with the app.MainLoop()</p>
  
  <p>Could someone confirm and/or explain a little bit more ?</p>
  
  <p>Thanks a lot,</p>
  
  <p>Patrick</p>