Chilled Cucumber Avocado Soup with Yogurt and Kefir

Ingredients: 1/2 avocado,5-6 persian cucumbers,small handful of grapes,juice of 1 lemon,1/2 cup plain kefir (can substitute buttermilk),1/2 cup plain Greek yogurt,1/4 cup chopped red onion,salt and pepper, to taste,4 scallions
Instructions:

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