Unable to import module 'app': No module named 'seeed_e5.py'

[nh-ee]

Hi,

I was following the guide here to build my own binary decoder in python. I deployed the CloudFormation stack along with decoder using SAM CLI. I see the stack created successfully. However, when I tried to test (just like 4. Create the test event of this guide here) the Lambda function, I got the following response

Test Event Name
IoTCoreForLoRaWANEvent

Response
{
  "errorMessage": "Unable to import module 'app': No module named 'seeed_e5.py'; 'seeed_e5' is not a package",
  "errorType": "Runtime.ImportModuleError",
  "stackTrace": []
}

What did I miss during deployment? Thank you for your time! @asvand