flyx

import win32api, win32con
import os, os.path
import struct
import math

def checkPath(path, mode):
    if not os.path.exists(path) or not os.path.isfile(path):
        raise ValueError("{0} does not exist or isn't a file.".format(path))
    if not os.access(path, mode):
        raise ValueError("Insufficient permissions: {0}".format(path))

jakevdp