import csv
ftr = [3600,60,1]
count = 0

with open('vboxmanage.csv', newline='') as csvfile:
    with open('new_vboxmanage.csv', mode = 'w') as newVbox:
        writer = csv.writer(newVbox, delimiter = ',')
        reader = csv.reader(csvfile, delimiter=',')
        for row in reader:
                #print(row)
                timeSS = row[0]
                timeSS = timeSS[11:20]
                #print(timeSS)
                timeSS = sum([a*b for a,b in zip(ftr, map(int,timeSS.split(':')))])
                #print(timeSS)

                if count == 0:
                    first = timeSS
                    count += 1

                timeSS = timeSS - first
                #print(timeSS)
                row[0] = timeSS
                #print(row)
                writer.writerow(row)
