All of the previous responses are great. I've also seen an additional line on Sch. E p. 2 for "Partnership Expenses" that could be utilized for this purpose. 

Here's the big question: What did they do last year? If this is the first year, I'd be hesitant to allow it for the reasons TaxGuyBill gave. If they did it last year, then just follow the same method, and keep impeccable notes in your work papers.

Why did the accountant cross the road? Because they looked in his PY work papers, and that's what they did last year.