OpenAI Assistants Agent (#4131)

* initial assistant client draft

* expose assistants client

* initial openai assistant agentchat draft

* update file search

* add delete methods and fix typing

* add tool execution

* fix tool call and add docstring

* abstract tools and support thread management

* add tests

* removed unused typevars

* add unsaved test changes

* test typing fixes

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Co-authored-by: Leonardo Pinheiro <[email protected]>

Author: lspinheiro

python/packages/autogen-agentchat/src/autogen_agentchat/agents/__init__.py

@@ -2,6 +2,7 @@
 from ._base_chat_agent import BaseChatAgent
 from ._code_executor_agent import CodeExecutorAgent
 from ._coding_assistant_agent import CodingAssistantAgent
+from ._openai_assistant_agent import OpenAIAssistantAgent
 from ._society_of_mind_agent import SocietyOfMindAgent
 from ._tool_use_assistant_agent import ToolUseAssistantAgent
 
@@ -11,6 +12,7 @@
     "Handoff",
     "CodeExecutorAgent",
     "CodingAssistantAgent",
+    "OpenAIAssistantAgent",
     "ToolUseAssistantAgent",
     "SocietyOfMindAgent",
 ]