_fileRepresentationMapping = {
'.png': NSPNGFileType,
'.gif': NSGIFFileType,
'.jpg': NSJPEGFileType,
'.jpeg': NSJPEGFileType,
'.bmp': NSBMPFileType,
'.tif': NSTIFFFileType,
'.tiff': NSTIFFFileType,
}



	def _getFileRepresentationType(filepath):
		base, ext = os.path.splitext(filepath)
		return _fileRepresentationMapping[ext.lower()]

	def screenshot(self, filepath):

	    # Take screenshot
	    rect = NSScreen.mainScreen().frame()
	    image = NSImage.alloc().initWithSize_((rect.size.width, rect.size.height))
	    screenRep = NSBitmapImageRep.alloc().initWithFocusedViewRect_(rect)
	    image.addRepresentation_(screenRep)

	    # Save
	    representation = _getFileRepresentationType(filepath)
	    data = image_rep.representationUsingType_properties_(representation, None)
	    data.writeToFile_atomically_(filepath, False)