TIL: boto3 can't parse env variables properly

So in today's saga of fighting the Internet, I bring this salient point to your attention:

boto3 can't parse environment variables for AWS credentials properly

and it will error kind of like this:

 ValueError: a Credential=WHACKADOODLEGGET5Q\r/20180627/us-east-1/sts/aws4_request

or possibly like this:

caught_exception\nValueError: Invalid header value '

    AWS4-HMAC-SHA256 Credential=WHACKADOODLET5Q\\r/20180627/us-east-1/ec2/aws4_request, SignedHeaders=content-type;host;x-amz-date, Signature=8f84f8d811f4dcb45da5f8fadf90ae8390d5d358b4024bf0d964090032dea1c3'\n", 

    "module_stdout": "", 

    "msg": "MODULE FAILURE", 

This appears to be an error in parsing the  \r portion of the URI. (Based on a few google queries.)

Using ~/.aws/credentials seems to do the trick (with the exact same key values):

[default]

aws_access_key_id=WHACKADOODLEGGGET5Q

aws_secret_access_key=bn+++krandometyperyforwhackadoodle1YjKMWqzv

The environment variables I was using were of course:

export AWS_ACCESS_KEY_ID=WHACKADOODLEGGGET5Q

export \ AWS_SECRET_ACCESS_KEY=bn+++krandometyperyforwhackadoodle1YjKMWqzv