Incorrect error check?

[MJohnson20]

https://github.com/nateshmbhat/webbot/blob/333f51840cd5a1fcde0b014bd6ab401d51e62860/webbot/webbot.py#L56

If specifying a path to a web driver in the selenium webdriver constructor it looks like it expects a full path, including the filename. However, this error checking of the passed driverPath into the webbot constructor (which is then passed to the webdriver constructor) checks to see if it's not a directory. This should probably check if it's not a file instead.