Update imports from langchain to langchain_core

[nandan2093]

Overview

Type of change

Type: [Replace with: New documentation page / Update existing documentation / Fix typo/bug/link/formatting / Remove outdated content / Other]

Related issues/PRs

• GitHub issue:
• Feature PR:

• Linear issue:
• Slack thread:

Checklist

• I have read the contributing guidelines
• I have tested my changes locally using docs dev
• All code examples have been tested and work correctly
• I have used root relative paths for internal links
• I have updated navigation in src/docs.json if needed
• I have gotten approval from the relevant reviewers
• (Internal team members only / optional) I have created a preview deployment using the Create Preview Branch workflow

Additional notes

[Copilot]

Pull Request Overview

This PR updates import statements to use the correct langchain_core.messages module instead of the non-existent langchain.messages module. This corrects a bug where imports were pointing to an invalid package location.

Key Changes:

• Corrected all imports from langchain.messages to langchain_core.messages throughout the quickstart documentation
• Affected imports include AnyMessage, SystemMessage, ToolMessage, and HumanMessage

[mdrxy]

Why?

[nandan2093]

@mdrxy

langchain.messages throws an import error as follows in python:

from langchain.messages import AnyMessage
ModuleNotFoundError: No module named 'langchain.messages'

Resolved this error by using langchain_core.messages

[Copilot]

Pull Request Overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated no new comments.

[mdrxy]

@nandan2093 please update your package.

https://reference.langchain.com/python/langchain/messages/#langchain.messages.AnyMessage