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I found this strange vegetable-looking plant growing randomly outside my apartment and was wondering what it is. It looks like a mustard family vegetable and the purple/green stem is similar to various mustard/broccoli species, but I am not sure what it is or even if it is edible. There are some flowers and it will soon form seeds.
Can someone help identify this plant for me? It grows very rapidly like a weed and the leaves are growing bigger each day.