catch LookUpError to return None
catch LookUpError to return None

- clusto pool 'dont-exist-yet-pool' shouldn't be throwing stacktraces
motivator/clusto,JTCunning/clusto,sloppyfocus/clusto,motivator/clusto,thekad/clusto,clusto/clusto,clusto/clusto,JTCunning/clusto,thekad/clusto,sloppyfocus/clusto