def test_formatFileSize(self):
        """
        L{static.formatFileSize} format an amount of bytes into a more readable
        format.
        """
        self.assertEqual(static.formatFileSize(0), "0B")
        self.assertEqual(static.formatFileSize(123), "123B")
        self.assertEqual(static.formatFileSize(4567), "4K")
        self.assertEqual(static.formatFileSize(8900000), "8M")
        self.assertEqual(static.formatFileSize(1234000000), "1G")
        self.assertEqual(static.formatFileSize(1234567890000), "1149G")

        L{static.formatFileSize} format an amount of bytes into a more readable
        format.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/web/test/test_static.py