如何在绘制csv时处理重复项？

import csv

def remove_duplicates(input_file, output_file):
    data = []
    duplicates = {}

    # 读取CSV文件并存储数据
    with open(input_file, 'r') as file:
        reader = csv.reader(file)
        header = next(reader)  # 读取表头
        data.append(header)
        for row in reader:
            data.append(row)

    # 处理重复项
    for row in data[1:]:
        key = tuple(row)  # 使用整个行作为关键字段
        if key in duplicates:
            duplicates[key] += 1
        else:
            duplicates[key] = 1

    # 删除重复项
    unique_data = [data[0]]  # 保留表头
    for row in data[1:]:
        key = tuple(row)
        if duplicates[key] == 1:
            unique_data.append(row)

    # 将数据写入CSV文件
    with open(output_file, 'w', newline='') as file:
        writer = csv.writer(file)
        writer.writerows(unique_data)

# 示例用法
input_file = 'input.csv'
output_file = 'output.csv'
remove_duplicates(input_file, output_file)