Таким образом, он будет сохранен в файлах, пронумерованных по номеру строки
import csv
with open('file.csv', 'r') as csv_file:
rows = csv.reader(csv_file, skipinitialspace=True)
for i, row in enumerate(rows):
with open('file_{}.csv'.format(i), 'w') as write_file:
writer = csv.writer(write_file)
writer.writerow(row)