How to convert date format "dd/mm/yy" to "yy/mm/dd" for mysql database inserting?

When I insert a date from a file that has it formatted "dd/mm/yy" into my database table with the date formatted "yy/mm/dd" the date is wrong:

Instead of getting 2019:04:11 I get 2011:04:19.

I want to keep the database format ("yy/mm/dd")

I have tried:

actualdate = DATE_FORMAT(j[0], '%y-%m-%d')

cursor.execute(actualdate)

but it tells me error: name 'DATE_FORMAT' is not defined

import mysql.connector
sql = mysql.connector.connect(host='',user='',password='',db='')

cursor = sql.cursor()
f = open("C:\Cumulus\data\Apr19log.txt","r")

st=[i.strip().split(',') for i in f.readlines()]

actualdate = DATE_FORMAT(j[0], '%y-%m-%d')  
cursor.execute(actualdate)

sqllist = "INSERT INTO station_fenelon (variable, date, time,             
outside_temp, outside_humidity) VALUES (%s, %s, %s, %s, %s)"
record = [(i+1, j[0], j[1], j[2], j[3]) for i, j in enumerate(st)]
cursor.executemany(sqllist, record)
sql.commit()

error: name 'DATE_FORMAT' is not defined