如何将DateTime变量赋值给flspots。另外，如何在flchart中为每个轴添加标题？

import java.time.LocalDateTime;

public class Main {
    public static void main(String[] args) {
        LocalDateTime dateTime = LocalDateTime.of(2022, 12, 31, 23, 59, 59); // 创建一个DateTime变量
        flspots = dateTime; // 将DateTime变量赋值给flspots
    }
}

from datetime import datetime

dateTime = datetime(2022, 12, 31, 23, 59, 59) # 创建一个DateTime变量
flspots = dateTime # 将DateTime变量赋值给flspots

import 'package:fl_chart/fl_chart.dart';

BarChart barChart = BarChart(
  BarChartData(
    // ...其他配置项
    axisTitleData: FlAxisTitleData(
      leftTitle: AxisTitle(
        showTitle: true,
        titleText: '左侧轴标题',
        textStyle: TextStyle(color: Colors.black),
      ),
      bottomTitle: AxisTitle(
        showTitle: true,
        titleText: '底部轴标题',
        textStyle: TextStyle(color: Colors.black),
      ),
    ),
  ),
);