Question about huma.WriteErr

[NeroBlackstone]

In huma middleware docs.

I don't know where dose the variable api come from?

func MyMiddleware(ctx huma.Context, next func(ctx huma.Context)) {
	// If there is a query parameter "error=true", then return an error
	if ctx.Query("error") == "true" {
               // WHERE DOSE THE VARIABLE API COME FROM
		huma.WriteErr(api, ctx, http.StatusInternalServerError,
			"Some friendly message", fmt.Errorf("error detail"),
		)
		return
	}

	// Otherwise, just continue as normal.
	next(ctx)
})