How to save Sankey diagram node positions after manual arrangement?

Question

I am trying to create Sankey diagrams with node positions using R and plotly package (https://plotly.com/r/sankey-diagram/#define-node-position).

library(plotly)

fig <- plot_ly(

  type = "sankey",

  arrangement = "snap",

  node = list(

    label = c("A", "B", "C", "D", "E", "F"),

    x = c(0.2, 0.1, 0.5, 0.7, 0.3, 0.5),

    y = c(0.7, 0.5, 0.2, 0.4, 0.2, 0.3),

    pad = 10), # 10 Pixel

  link = list(

    source = c(0, 0, 1, 2, 5, 4, 3, 5),

    target = c(5, 3, 4, 3, 0, 2, 2, 3),

    value = c(1, 2, 1, 1, 1, 1, 1, 2)))

fig <- fig %>% layout(title = "Sankey with manually positioned node")


fig

However, the default node positions are not good enough. So I need to manually adjust the node positions from the interactive plot. However, I need to save the new positions and update the positions in the script. Then next time when I run the script again, I don't need to adjust the positions manually again?

Is there anyway to save node positions after manual arrangement?