title: Use wxPython.FileDialog to save file
body: <p>I am using <code>wx.FileDialog</code> to pop a directory select dialog for the user to choose the save path. The file type I'd like to save is <code>.csv</code> files.</p>
  
  <p>Here is the code:</p>
  
  <pre><code>fdlg = wx.FileDialog(self.panel_settings, "Input setting file path", "", "", "CSV files(*.csv)|*.*", wx.FD_SAVE)
  
  if fdlg.ShowModal() == wx.ID_OK:
      self.save_path = fdlg.GetPath() + ".csv"
  
  with open(self.save_path, "wb") as file:
      writer = csv.writer(file, delimiter = ',')
  </code></pre>
  
  <p>When a dialog pops up, I simply type in <code>test</code> as the file name. As I click <code>OK</code> button, it directly save an empty <code>test.csv</code> file.</p>
  
  <p>However, what I want to do is just keep the input path and file name, then write the content myself.</p>
  
  <p>So, may I know how to work around this?</p>
  
  <p>Thanks.</p>