Guard clause example

guard.py

email_obj = process_email(email_string)
if email_obj.has_data:
    if email_obj.has_images or email_obj.has_unsupported_images:
        process_images(email_obj.images)
    else:
        process_text(email_obj.text)
else:
    raise InvalidEmail
    

# with guard clause
email_obj = process_email(email_string)
if not email_obj.has_data:
    raise InvalidEmail
    
if email_obj.has_images or email_obj.has_unsupported_images:
    process_images(email_obj.images)
else:
    process_text(email_obj.text)