如何在图形标题中写入列的值？

import matplotlib.pyplot as plt
import pandas as pd

# 示例数据
data = {'Year': [2019, 2020, 2021], 'Sales': [100, 150, 200]}
df = pd.DataFrame(data)

# 创建图表
plt.figure(figsize=(10, 6))
plt.plot(df['Year'], df['Sales'])

# 设置标题并动态显示列的值
title = f"Sales: {df['Sales'].iloc[-1]}"
plt.title(title)

plt.show()

// 示例数据
const data = [
  { year: 2019, sales: 100 },
  { year: 2020, sales: 150 },
  { year: 2021, sales: 200 }
];

// 创建SVG元素
const svg = d3.select("body").append("svg")
    .attr("width", 500)
    .attr("height", 300);

// 绘制折线图
const line = d3.line()
    .x(d => xScale(d.year))
    .y(d => yScale(d.sales));

svg.append("path")
    .datum(data)
    .attr("fill", "none")
    .attr("stroke", "steelblue")
    .attr("stroke-width", 1.5)
    .attr("d", line);

// 设置标题并动态显示列的值
const lastYearSales = data[data.length - 1].sales;
svg.append("text")
    .attr("x", 250)
    .attr("y", 20)
    .attr("text-anchor", "middle")
    .style("font-size", "16px")
    .text(`Sales: ${lastYearSales}`);