Using ordered dictionary to copy pcap files

#!/bin/env python3
#_*_coding:UTF-8_*_
import dpkt
import collections
import time
def main(file_path,filewr_path):
    f=open(file_path,mode='rb')
    try:
        pcap=dpkt.pcap.Reader(f)
    except:
        pcap=dpkt.pcapng.Reader(f)
    all_pcap_data=collections.OrderedDict()
   
    count=0
    for(ts,buf) in pcap:
        # Here, we can add a target for buf The processing code of , This is read in pcap File processing buf
        all_pcap_data[count]=(ts,buf)
        count=count+1
    f.close()
    
    f=open(filewr_path,mode='wb')
    pcap=dpkt.pcap.Writer(f)
    
    for i in all_pcap_data:
        # You can also add here for buf The processing code of , This is written to pcap File processing buf
        pcap.writepkt(all_pcap_data.get(i)[1],ts=all_pcap_data.get(i)[0])
    f.close()

if __name__=='__main__':
    file_path="./project3.pcap"
    filewr_path="./project3bak.pcap"
    main(file_path,filewr_path)

The source file is project3.pcap, The file name after copying is project3bak.pcap, Code can be added in the middle to extract each package 、 Filtering and other operations