I'm trying to raise an error when a directory does not exist, before I open files in that directory. According to this response I should use the most specific Exception constructor for my issue, which I think is
NameError: global name 'NotADirectoryError' is not defined
if not os.path.isdir(baselineDir):
raise NotADirectoryError("No results directory for baseline.")
You're likely using Python 2, which does not define
NotADirectoryError. However, this is defined in Python 3, for exactly the purpose you're trying to use it for.
If you need to use Python 2, you'll need to define the error yourself through a class. Read through the docs about user-defined exceptions to learn about subclassing the
Exception class and customizing it for your own needs, if necessary. Here's a very simple example:
class NotADirectoryError(Exception): pass
This will take the string passed to it and print it out, just like you want.