Lambda function python package import problem

Question

```
import json
import langchain
from langchain import LLMChain
def lambda_handler(event, context):
    # res = test_endpoint()
    # res = "lambda is running"
    # TODO implement
    return {
        'statusCode': 200,
        'body': json.dumps('Hello from Lambda!')
    }
```
When I import langchain only it is not throwing any error but when I``` import from langchain import LLMChain``` gives error {
  "errorMessage": "Unable to import module 'lambda_function': No module named 'pydantic_core._pydantic_core'",
  "errorType": "Runtime.ImportModuleError",
  "requestId": "c29d10cc-d012-4eb8-acb1-468537d4d708",
  "stackTrace": []
}
I have added in layer langchain package zip.

Answer

Hi,

In lambda, it's not possible to import modules from https://pypi.org. It supports only boto3 and all default modules under python package, none other. To sort this out, I would suggest to install modules in present non-default directory in your local system by using below command, so that you will see the modules are installed in your present directory. Post that you can zip module files with your code together, then upload it to lambda.

Command: pip install  -t . --no-user

Answer

Hi,

Some other folks are having similar problem when running Lambdas on ARM: https://github.com/pydantic/pydantic/issues/6557

It seems that the solution is to use Lambda runtime 3.10 or above.

Can you try that?

Best,

Didier

Lambda function python package import problem

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