使用python将csv中的值插入到日期和小时相同的另一个csv中

import csv
from datetime import datetime

def parse_datetime(datetime_str):
    return datetime.strptime(datetime_str, "%Y-%m-%d %H:%M:%S")

def insert_values(source_csv, target_csv):
    with open(source_csv, 'r') as source_file, open(target_csv, 'a', newline='') as target_file:
        source_reader = csv.reader(source_file)
        target_writer = csv.writer(target_file)
        
        for row in source_reader:
            source_datetime = parse_datetime(row[0])
            source_value = row[1]
            
            # 在目标CSV文件中查找相同日期和小时的行
            target_file.seek(0)
            target_reader = csv.reader(target_file)
            target_rows = list(target_reader)
            target_row_index = -1
            
            for i, target_row in enumerate(target_rows):
                target_datetime = parse_datetime(target_row[0])
                
                if source_datetime.date() == target_datetime.date() and source_datetime.hour == target_datetime.hour:
                    target_row_index = i
                    break
            
            # 如果找到匹配的行，则将值插入到该行中
            if target_row_index != -1:
                target_rows[target_row_index].append(source_value)
            else:
                # 如果没有找到匹配的行，则创建一个新行并插入值
                new_row = [source_datetime.strftime("%Y-%m-%d %H:%M:%S"), source_value]
                target_rows.append(new_row)
            
            # 将更新后的行写入目标CSV文件
            target_file.seek(0)
            target_writer.writerows(target_rows)

insert_values('source.csv', 'target.csv')