'com.inductiveautomation.perspective.gateway.script' object has no attribute 'active_call'

[lrose]

might also be another gotcha from this:

calls = self.custom.active_calls

@pbg See this thread:

[IGN-1660]PSA - Assigning values to a property in a script may drive you nuts

Among other things, basically, don't do this. You're capturing the 'property tree' wrapper housed at self.custom.data in your script. Mutations are primarily forwarded to the actual backing store (because that's what matters, and what syncs to the frontend) and there's a longstanding bug where the local instance you have doesn't reflect those updates correctly. It's mostly been a nuisance bug because the typical pattern (referring to component props fully qualified all the time) avoids it.