<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 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)