How to cron job setup in Amazon ec2

Question

I have an Amazon EC2 instance running my website. I need to setup a Cron Job to run my file every 12hours.

if file setup via command line so please give a detail ste

Answer 1

I recently began using Amazon's linux distro on ec2 instances and after trying all kinds of things for cron all I needed was:
sudo service crond start
crontab -e
This allowed me to set a cron job as "ec2-user" without specifying the user. For example:
0 12 * * * python3 example.py
In fact, specifying a user here prevented it from running. I also posted this here.