Jobs scheduled using python_crontab not working

Question

I am using following python code to schedule job in ubuntu.

from crontab import CronTab
cron = CronTab(user='username')
job = cron.new(command='/usr/bin/python3 /home/(user)/Desktop/Schedular/ScheduleInvoicingUtility.py >> /home/(user)/Desktop/Schedular/Logs.txt')
job.setall('*/2 * * * *') 
cron.write()
print(cron.render())

Code run successfully, and it's render function print output as follow:

*/2 * * * * /usr/bin/python3 /home/(user)/Desktop/Schedular/ScheduleInvoicingUtility.py >> /home/(user)/Desktop/Schedular/Logs.txt

But do not know where this job is saved in ubuntu, and also job is not running/working after specified time.

Any idea what I am doing wrong?

• Jean-François Fabre: don't you need admin rights to alter the crontable?
• Waqas Ali: I can edit crontab using sudo crontab -e command, and i used same user above in my python code.
• Jean-François Fabre: so you ran your pyhton script using sudo ?
• Waqas Ali: This python script is being triggered by another cron job. code of cron job is: 0 7 * * * /usr/bin/python3 /home/(user)/Desktop/Schedular/ScheduleInvoicingUtility.py >> /home/(user)/Desktop/Schedular/Logs.txt
• Jean-François Fabre: I mean: run the python script corresponding to the snippet using sudo, no the Invoicing thingy.

Answer 1

Finally i fix the issue with minor changes. Here is code which is properly creating the cron job from python:

cron = CronTab(user=True)
job = cron.new(comment='My_Unique_Job', command='/usr/bin/python3 /home/(user)/Desktop/Schedular/ScheduleInvoicingUtility.py >> /home/(user)/Desktop/Schedular/Logs.txt')
job.setall('*/2 * * * *')
cron.write()

Use this to remove previous jobs with same id.

cron.remove_all(comment='My_Unique_Job')

Complete code will be:

cron = CronTab(user=True)
cron.remove_all(comment='My_Unique_Job')
job = cron.new(comment='My_Unique_Job', command='/usr/bin/python3 /home/(user)/Desktop/Schedular/ScheduleInvoicingUtility.py >> /home/(user)/Desktop/Schedular/Logs.txt')
job.setall('*/2 * * * *')
cron.write()

Don't forgot to import CronTab:

from crontab import CronTab

Install python_crontab using pip.

pip install python_crontab