R notebook with embedded shinyapp : Pass a variable from shinyapp chunk to next code chunk

Question

I would like to embed several standard and shinyApp chunks of R code in R notebook:

I start with YAML

---
title: "R Notebook"
output: html_notebook
runtime: shiny
---

Next I load libraries

```{r}
library(tidyverse)
head(iris)
iris1<-iris %>% select(-c(Petal.Length, Petal.Width))
```

Next I use a kmeans example https://shiny.rstudio.com/gallery/kmeans-example.html

```{r, echo = FALSE, }
shinyApp(

  ui = pageWithSidebar(
  headerPanel('Iris k-means clustering'),
  sidebarPanel(
    selectInput('xcol', 'X Variable', names(iris)),
    selectInput('ycol', 'Y Variable', names(iris),
                selected=names(iris)[[2]]),
    numericInput('clusters', 'Cluster count', 3,
                 min = 1, max = 9)
  ),
  mainPanel(
    plotOutput('plot1')
  )
),

  server = function(input, output) {

         selectedData <<- reactive({
          iris[, c(input$xcol, input$ycol)]
        })

        clusters <- reactive({
          kmeans(selectedData(), input$clusters)
        })

        output$plot1 <- renderPlot({
          palette(c("#E41A1C", "#377EB8", "#4DAF4A", "#984EA3",
            "#FF7F00", "#FFFF33", "#A65628", "#F781BF", "#999999"))

          par(mar = c(5.1, 4.1, 0, 1))
          plot(selectedData(),
               col = clusters()$cluster,
               pch = 20, cex = 3)
          points(clusters()$centers, pch = 4, cex = 4, lwd = 4)
        })

      },
  options=list(height="700")
)
```

Now I would like to use the clusters variable in the next chunk. Can it be made available globally? Or rendered to a variable that I can use in the next chunk? I was thinking maybe about writing a csv and then making an option to read csv in the next chunk.