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Hi everyone,

I couldn't find this in the documentation anywhere, so thought I'd try here. Does anyone know what the last_sale_date is in context.portfolio.positions? I ran a few tests and saw that it was the buy date of my securities. I'm still learning Python so I haven't been able to check how selling some of the shares affects it yet but I'd imagine it would change based on its name.



2 responses

I believe it's the last time you had an order (technically, got a fill) in the given security. Any time you buy or sell in that security it will be updated.

This isn't documented, as you note, and I'm not sure what it would be used for. To figure out where it came from I looked it up in Zipline, the open source backtester we are built on. I believe it is set in line 144 of


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Ok, thanks Dan. I haven't really gone through Zipline much yet - I just tried to a little and it seemed a little out of reach for me for now - but hopefully I'll get there eventually.