Python 如何在多处理中运行concat？

我想做两个合并文件的程序并行通过多处理。他们每个人都将数十个文件合并成一个文件。写它的正确语法是什么

没有多重处理，运行正常

tripnames = [filename for filename in os.listdir(paths.outPath) if filename.startswith("trips")]
odnames = [filename for filename in os.listdir(paths.outPath) if filename.startswith("workOD")]

combined_csv = pd.concat([pd.read_csv(paths.outPath + f) for f in tripnames])
combinedOD_csv = pd.concat([pd.read_csv(paths.outPath + f) for f in odnames])

combined_csv.to_csv( paths.outPath + "trips.csv", index=False, encoding='utf-8-sig')
combinedOD_csv.to_csv( paths.outPath + "workOD.csv", index=False, encoding='utf-8-sig')

多处理

tripnames = [filename for filename in os.listdir(paths.outPath) if filename.startswith("trips")]
odnames = [filename for filename in os.listdir(paths.outPath) if filename.startswith("workOD")]
combined_csv = Process(target=pd.concat([pd.read_csv(paths.outPath + f) for f in tripnames]))
combinedOD_csv = Process(target=pd.concat([pd.read_csv(paths.outPath + f) for f in odnames]))
combined_csv.start()
combinedOD_csv.start()
combined_csv.join()
combinedOD_csv.join()            
exe_tripMerge = Process(target=combined_csv.to_csv(paths.outPath + "trips.csv", index=False, encoding='utf-8-sig'))
exe_workODMege = Process(target=combinedOD_csv.to_csv(paths.outPath + "workOD.csv", index=False, encoding='utf-8-sig'))
exe_tripMerge.start()
exe_workODMege.start()
exe_tripMerge.join()
exe_workODMege.join()

我犯的错误是

ValueError: The truth value of a DataFrame is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all().
Traceback (most recent call last):
File "runrtm.py", line 157, in <module>
    main()
File "runrtm.py", line 112, in main
    combined_csv = Process(target=pd.concat([pd.read_csv(paths.outPath + f) for f in tripnames]))
AttributeError: 'Process' object has no attribute 'to_csv'

ValueError：数据帧的真值不明确。使用a.empty、a.bool（）、a.item（）、a.any（）或a.all（）。
回溯（最近一次呼叫最后一次）：
文件“runrtm.py”，第157行，在
main（）
文件“runrtm.py”，主目录第112行
组合的_csv=Process（target=pd.concat（[pd.read_csv（path.outPath+f）表示tripnames中的f]））
AttributeError:“进程”对象没有属性“到”

我正在寻找正确的语法。提前谢谢