Issue with AWS Sam invoking local lambda

Question

I have a python lambda which is just the sample hello_world which you can create using sam init.

I have modified it slightly by adding sub-folder in the lambda folder.

So inside the hello_world lambda folder I have:

app.py # this is the lambda handler
requirements.txt
my_code_folder # I added this and I want to be able to import it and use it in the lambda. It contains a tonne of custom modules.

However when I run sam local invoke I get:

[ERROR] Runtime.ImportModuleError: Unable to import module 'app': No module named 'hello_world'

If I take out the import it works fine.

Perhaps I have imported incorrectly in my lambda?

import hello_world.my_code_folder.MyModule as my_module

My SAM template has this:

Globals:
  Function:
    Timeout: 3

Resources:
  HelloWorldFunction:
    Type: AWS::Serverless::Function # More info about Function Resource: https://github.com/awslabs/serverless-application-model/blob/master/versions/2016-10-31.md#awsserverlessfunction
    Properties:
      CodeUri: hello_world/
      Handler: app.lambda_handler
      Runtime: python3.8
      Events:
        HelloWorld:
          Type: Api # More info about API Event Source: https://github.com/awslabs/serverless-application-model/blob/master/versions/2016-10-31.md#api
          Properties:
            Path: /hello
            Method: get

Answer 1

Sample app created using sam init command and added a custom module named hello

❯❯ cat hello_world/hello/hello_world.py
# custom module
def hello():
    print("hello")

❯❯ cat hello_world/app.py
import json
import hello.hello_world as h


def lambda_handler(event, context):
...
    h.hello()

    return {
        "statusCode": 200,
        "body": json.dumps({
            "message": "hello world",
            # "location": ip.text.replace("\n", "")

directory structure

/tmp/foo/samapp via 🐍 v3.8.2 ((samapp))
❯❯ tree
.
..
├── __init__.py
├── events
│   └── event.json
├── hello_world
│   ├── __init__.py
│   ├── app.py
│   ├── hello. <--- my custom module
│   │   └── hello_world.py
│   └── requirements.txt
├── samconfig.toml
├── template.yaml

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