interface CompletionUsageimport { type CompletionUsage } from "https://deno.land/x/openai@v4.21.0/resources/mod.ts"; Usage statistics for the completion request. Propertiescompletion_tokens: numberNumber of tokens in the generated completion. prompt_tokens: numberNumber of tokens in the prompt. total_tokens: numberTotal number of tokens used in the request (prompt + completion).