一定時間ごとに保存されるデータをエクセルに記入したい

#ーーーwatchdogsでファイルを監視ーーー
import openpyxl
import time
import os

from watchdog.events import PatternMatchingEventHandler
from watchdog.observers import Observer

def exl_write(kekka, excel_filepath):
    time_start = time_now = time.time()
    line_num = 1
    wb = openpyxl.load_workbook('result.xltx')
    # シートを取得
    ws = wb.active
    # セルへ書き込む
    while True:
        if (time_now - time_start < 10):
            break      
        ws.cell(line_num,1).value = kekka
        
    # 保存する
    book.save(excel_filepath + 'data.xlsx')

class MyHandler(PatternMatchingEventHandler):
    def __init__(self, patterns):
        super(MyHandler, self).__init__(patterns=patterns)

    def on_created(self, event):
        filepath = event.src_path
        filename = os.path.basename(filepath)
        print(filename)
        
        kekka= test() #ここで計算を行う
        
        excel_filepath = file_path.removeprefix(filename)
        exl_write(kekka)


def watch(path):
    extensions = ["*.csv"]
    event_handler = MyHandler(extensions)
    observer = Observer()
    observer.schedule(event_handler, path, recursive=True)
    observer.start()
    try:
        while True:
            time.sleep(1)
    except KeyboardInterrupt:
        observer.stop()
    observer.join()

if __name__ == "__main__":
    path = os.path.dirname(os.path.abspath(__file__))
    watch(path)