I have gotten solution to my question above 🙂 . Since I used wxpython for my GUI, there is a demo code on SplashScreen and AdvancedSplash things available within wxpython demo software.
By the way @TLama, thanks for point to me the technical name of this functionality.
Here are the working codes;
#For wx.SplashScreen
bitmap = wx.Bitmap('splashImage.png', wx.BITMAP_TYPE_PNG)
splash = wx.SplashScreen(bitmap, wx.SPLASH_CENTRE_ON_SCREEN | wx.SPLASH_TIMEOUT, 10000, None, style = wx.SIMPLE_BORDER | wx.STAY_ON_TOP | wx.SPLASH_CENTRE_ON_PARENT)
wx.Yield()
#wx.AdvancedSplash
import wx
import wx.lib.agw.advancedsplash as AS
app = wx.App(0)
frame = wx.Frame(None, -1, "AdvancedSplash Test")
imagePath = "my_splash_image.png"
bitmap = wx.Bitmap(imagePath, wx.BITMAP_TYPE_PNG)
shadow = wx.WHITE
splash = AS.AdvancedSplash(frame, bitmap=bitmap, timeout=5000, agwStyle=AS.AS_TIMEOUT | AS.AS_CENTER_ON_PARENT | AS.AS_SHADOW_BITMAP, shadowcolour=shadow)
app.MainLoop()
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