change desktop

import wx
import os
import shutil
import ctypes


class Window(wx.Frame):
    def __init__(self, parent, id):
        self.dPics = "C:\Desktop background"
        self.list = []
        self.SPI_SETDESKWALLPAPER = 20
        no_caption = wx.DEFAULT_FRAME_STYLE | wx.STAY_ON_TOP
        wx.Frame.__init__(
            self, parent, id, title="no_caption",
            size=(300, 105), style=no_caption)
        self.panel = wx.Panel(self)
        self.cBack = wx.Button(
            self.panel, -1, label="Change",
            pos=(0, 0), size=(100, 70))
        self.cBack.Bind(wx.EVT_BUTTON, self.ChangeDesk, self.cBack)
        self.dPicsFull = os.listdir(self.dPics)
        self.counter = 0
        for self.items in self.dPicsFull:
            self.fullPath = os.path.join(self.dPics, self.items)
            if self.fullPath.endswith(('.jpg', '.png')):
                self.list.append(self.fullPath)

    def ChangeDesk(self, e):
        ctypes.windll.user32.SystemParametersInfoA(
            self.SPI_SETDESKWALLPAPER, 0, self.list[self.counter], 3)
        self.counter += 1
        if self.list[self.counter] == self.list[-1]:
            self.counter = 0

if __name__ == '__main__':
    app = wx.App(False)
    frame = Window(parent=None, id=-1)
    frame.Show()
    app.MainLoop()