module 'DNS' has no attribute 'Type'

@jsf9k hi! I am trying to run trustymail in a Lambda function but keep running into the same issue over and over again. I am using the provided `lambda_handler.py` and I am getting the same error as when I tried using trustymail from the `lambda_functions` repository. Is there a solution to this problem? Can I be put in touch with folks that are being able to successfully run trustymail on their boxes so I understand how they are doing it? I would appreciate ANY help I get from you guys on this, I have been struggling for way too long :(

`START RequestId: fd3b5a22-82e1-4f05-8ef6-e419847b67a3 Version: $LATEST
2019-07-15 15:29:16,183 INFO AWS Event was: {'domain_name': 'dhs.gov'}
module 'DNS' has no attribute 'Type': AttributeError
Traceback (most recent call last):
File "/var/task/lambda_handler.py", line 98, in handler
from trustymail.trustymail import scan
File "/var/task/trustymail/trustymail.py", line 11, in
import spf
File "/var/task/spf.py", line 111, in
if not hasattr(DNS.Type, 'SPF'):
AttributeError: module 'DNS' has no attribute 'Type'`

Related to: https://github.com/cisagov/trustymail/issues/41