[BUG]: "No module named 'langchain_core'" when updating ddtrace from v2.16.x

[bayshann-matt-chamberlain]

Tracer Version(s)

2.16.4

Python Version(s)

3.11.11, 3.13.3

Pip Version(s)

25.1

Bug Report

When we upgrade past version 2.16.4 (2.17.x) onwards, we see this error. If we add the langchain package explicitly, the problem is solved.

It seems to be related to the 2.17 where I'm guessing langchain was introduced? https://github.com/DataDog/dd-trace-py/releases/tag/v2.17.0

Is there an expectation that we need to include langchain? If so is it in the documentation somewhere? Would it be better to include the package as part of your dependencies?

Thanks!

Reproduction Code

No response

Error Logs

[ERROR] Runtime.ImportModuleError: Unable to import module 'datadog_lambda.handler': No module named 'langchain_core'

Libraries in Use

• datadog-lambda v6.107.0
• lambda-extension public.ecr.aws/datadog/lambda-extension:77

Operating System

Linux 7ec7c6b4859e 6.10.14-linuxkit #1 SMP Tue Apr 15 16:00:54 UTC 2025 x86_64 x86_64 x86_64 GNU/Linux (Amazon Linux 2023.7.20250331)