py3 execfile实现

def execfile(file_path, globals=None, locals=None):
    if globals is None:
        globals = {}
    globals.update({
        "__file__": file_path,
        "__name__": "__main__",
    })
    with open(file_path, 'rb') as file:
        exec(compile(file.read(), file_path, 'exec'), globals, locals)