We have black snakes, and they are welcome, because since we have them, we don't have rattlers, and other poisonous snakes. Once in a while the girls will startle one out, but we won't let them hurt the snake. I have seen them come sliding down the roof and off the awning, lol. Does give you a bit of a surprise, but not near as much as it did the frog it was after.
I would prefer them to stay OUTSIDE, and tell them that when I see them. During Wilma, there was a small snake right inside the screen. We left it there until the storm passed, then opened the door and shooed it back out.