Pool args fix

[segasai]

Address #464

[coveralls]

Pull Request Test Coverage Report for Build 7173093321

• 12 of 12 (100.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.01%) to 91.678%

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Totals
Change from base Build 7105543502:	-0.01%
Covered Lines:	4153
Relevant Lines:	4530

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💛 - Coveralls

[segasai]

Thanks for taking a look. I accepted your doc edit, but I didn't catch what you meant by this (or whether it was what exactly about your doc edit)

One minor doc suggestion though, just to make sure the user catches that the concatenation behavior happens.

I think the concatenation is mentioned now both in pool.py, and docs (and I don't think the runtime warning is needed here)