spotify/luigi — pull request #293 by JonNelson (2014-03-15 02:46:13+00:00)
Title: - fix serialization of DataHourParameter when the value is None

DateParameter, like most (all?) other Parameter-derived types, can be None, at least for serialization purposes. However, DateHourParameter can't, and this fixes that situation.

Oftentimes I find myself using None as a default and then in 'depends' checking for a value of None and replacing the value with a new value calculated on-the-fly.