Addressing issue with single output from node being an array

[anomam]

Fix for issue #4

[cedricleroy]

Thanks for the PR, Marc. It fails the tests because of the use of numpy and this line. I would like to limit the dependencies if not absolutely needed, so I pushed this pure Python alternative. Let me know if it works, I like your use of squeeze as it may be a more global solution that cover cases I am not really seeing right now.

[anomam]

Ok, I just saw that you created a whole new PR for this.
Because I'm importing functions from another package, I do need to squeeze the returned values for the dag to work. But no need to add a dependency on numpy indeed, I just created a decorating function in my script that wraps the imported functions to squeeze their results.
Also, I think that it may be a little harsh to raise an exception when an input is not used, but I can see arguments for having it also. So no worries.
I'm closing this PR in favor of your solution.
Thanks