如何获得png或jpeg或bmp图片在wxpython

我想搜索png, jpeg和bmp图片，但它似乎不工作。

def onClick(self,Event):
        wildcard='PNG files (*.png)|*.png|'|'BMP files (*.bmp)|*.bmp|'|'JPEG files (*.jpg)|*.jpg|'
        openFileDialog = wx.FileDialog(self, "Open", "", "", wildcard,wx.FD_OPEN | wx.FD_FILE_MUST_EXIST)
        openFileDialog.ShowModal()

这是错误，我不知道如何解决

wildcard='PNG files (*.png)|*.png|'|'BMP files (*.bmp)|*.bmp|'|'JPEG files (*.jpg)|*.jpg|'
TypeError: unsupported operand type(s) for |: 'str' and 'str'

问题来源StackOverflow 地址：/questions/59384186/how-to-get-png-or-jpeg-or-bmp-pictures-in-wxpython