如何将数据框的列表行转换为字符串？

import pandas as pd

# 创建数据框
df = pd.DataFrame({'A': [1, 2, 3], 'B': [4, 5, 6]})

# 将列表行转换为字符串
string_representation = df.to_string(index=False)

print(string_representation)

 A  B
 1  4
 2  5
 3  6

import org.apache.commons.csv.CSVFormat;
import org.apache.commons.csv.CSVPrinter;

import java.io.StringWriter;
import java.io.PrintWriter;
import java.util.Arrays;

// 创建数据框
List<List<String>> data = Arrays.asList(
    Arrays.asList("A", "B"),
    Arrays.asList("1", "4"),
    Arrays.asList("2", "5"),
    Arrays.asList("3", "6")
);

// 创建StringWriter用于接收输出
StringWriter writer = new StringWriter();

// 创建CSVPrinter
CSVPrinter csvPrinter = new CSVPrinter(writer, CSVFormat.DEFAULT);

// 将列表行写入CSVPrinter
for (List<String> row : data) {
    csvPrinter.printRecord(row);
}

// 关闭CSVPrinter
csvPrinter.close();

// 获取字符串表示
String stringRepresentation = writer.toString();

System.out.println(stringRepresentation);

A,B
1,4
2,5
3,6