Adds custom images to Artprovider

def CreateBitmap(self, artid, client, size):
        """Adds custom images to Artprovider"""

        if artid in self.extra_icons:
            return wx.Bitmap(self.extra_icons[artid], wx.BITMAP_TYPE_ANY)

        else:
            return wx.ArtProvider.GetBitmap(artid, client, size)