You're seeing just the function unpack_ast, go back to ExOpenAI.Components.ChatCompletionRequestMessage module for more information.
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unpack_ast(partial_tree \\ %{})

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Helper function to return the full AST representation of the type and all it's nested types This is used so that all atoms in the map are getting allocated recursively. Without this, we wouldn't be able to safely do String.to_existing_atom()