Remove shadows around wx.Region

wxPython Users
#1

When you click inside the wx.Region, a drop shadow appears around the shaped window when it has focus and disappears when you click outside. When you have multiple regions close to each other, the shadows are distracting. Is there a way to disable to the shadows around wx.Regions?
# Set mask color.
maskColour = wx.Colour(0, 0, 0)

        # Get width and height.
        width, height = self.GetSize()

        # Create empty bitmap.
        bitmap = wx.Bitmap(width, height)
        dc = wx.MemoryDC(bitmap)

        # Draw empty bitmap with mask colors.
        dc.SetBrush(wx.Brush(maskColour))
        dc.DrawRectangle(0, 0, width, height)

        # Set pen color.
        dc.SetPen(wx.Pen(self.GetBackgroundColour(), style=wx.PENSTYLE_SOLID))
       .......
       ........
       ........
       # Reset memory DC.
        dc.SelectObject(wx.NullBitmap)
        bitmap.SetMaskColour(maskColor)

        # Set shape.
        self.SetShape(wx.Region(bitmap))