code: def tooltip_text(row, rounding_function, digits):
      if row.difference > 0:
          key_word = "+"
      else:
          key_word = "-"
      return (
          "Model: "
          + str(row.label)
          + " loss after<br>variable: "
          + str(row.variable)
          + " is permuted: "
          + str(rounding_function(row.dropout_loss, digits))
          + "<br>"
          + "Drop-out loss change: "
          + key_word
          + str(rounding_function(np.abs(row.difference), digits))
      )
  
label_desc: Use image node_id 1 for calling a global function with example usage: tooltip_text(row, rounding_function, digits) and returns: unknown