Support functions removing in ConversableAgent

[skzhang1]

Why are these changes needed?

there are scenarios where we not only need to register functions but also remove previously registered ones in UserProxyAgent. Similar to the existing update_function_signature in the assistant, we also need an interface to remove functions in UserProxyAgent.

Related issue number

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[codecov-commenter]

Codecov Report

Attention: Patch coverage is 60.00000% with 2 lines in your changes are missing coverage. Please review.

Project coverage is 48.02%. Comparing base (c6f6707) to head (f4b2c51).

Files	Patch %	Lines
autogen/agentchat/conversable_agent.py	60.00%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #1786       +/-   ##
===========================================
+ Coverage   36.96%   48.02%   +11.05%     
===========================================
  Files          62       62               
  Lines        6525     6528        +3     
  Branches     1445     1571      +126     
===========================================
+ Hits         2412     3135      +723     
+ Misses       3920     3144      -776     
- Partials      193      249       +56     

Flag	Coverage Δ
unittests	47.94% <60.00%> (+10.98%)	⬆️

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[BeibinLi]

This new feature looks good to me.

However, the usage of using "None" for removal inside a "register" function might be a little bit confusing for some users. If we can change this function name to "update_function_registration", it would be more correct...

Let's forget about the function name for backward compatibility for now.

[skzhang1]

@BeibinLi Agree. We may consider changing the function name in future PR.

[LeoLjl]

I agree with @BeibinLi. Setting parameters to None to remove functions seems not a straightforward way and can cause confusion. The code looks good to me.

[ekzhu]

Perhaps we can create a new function update_function_map which updates the function map, with two arguments: to_add, which is a dictionary, and to_remove, which is a list of function names. Would that work? Meanwhile we put a deprecation notice to the register_function and re-implement that to use update_function_map.

Though I still would like to understand the usage case and why you need to have this feature.

[skzhang1]

@ekzhu I’m currently working on the AutoGen learning component. Having a convenient API to manipulate registered functions is crucial for me.
#1767 (review)

[skzhang1]

Perhaps we can create a new function update_function_map which updates the function map, with two arguments: to_add, which is a dictionary, and to_remove, which is a list of function names. Would that work? Meanwhile we put a deprecation notice to the register_function and re-implement that to use update_function_map.

Though I still would like to understand the usage case and why you need to have this feature.

Good suggestion. I will make it in the next PR. We can merge this one first.