send email to local directory instead of mailserver

send email to local directory instead of mailserver

I have written a python piece of code to send email using SMTP.
I have used smtplib. It's working fine.
I want to simulate a scenario where many users would send email. So to
avoid overloading the server I want that message should not be stored on
mail server. Instead they should be stored in a local directory. But the
mail server should be hit.
How can go about doing this in python