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Issue Content

Currently there's a bunch of tools and other integrations that use initialize_agent in their docs page (search langchain/docs for "initialize_agent")

This function has been deprecated since 0.1 and should be replaced with basic langgraph usage as a demo

Deprecated function: https://python.langchain.com/api_reference/langchain/agents/langchain.agents.initialize.initialize_agent.html

Example page using create_react_agent in an example: https://python.langchain.com/docs/integrations/tools/gmail/#use-within-an-agent

This issue doesn't need to be resolved by a single PR and can be tackled incrementally! Just tag this issue for tracking purposes :)