I currently have a csv file containing a column of dates that is formatted as dd/mm/yyyy but i want to change it to yyyy/mm/dd

I have written the code below:

```
import csv
csv_in = open('news.csv','rb')

for rows in csv.reader(csv_in):
    value = rows[0]
    day= value[:2]
    year= value[-4:]
    month= value[3:5]
    edited = year +'/'+month+'/'+day
    rows[0] = edited
    writer =csv.writer(open('newsedit.csv', 'wb'))
    writer.writerow(rows)

```

for some reason the code above will only write one row and stop and i can't seem to figure out why this is happening.