SolveMathProblem.swift

import Foundation
import LangChain
import PythonKit

func solveMathProblem(_ problem: String) async throws -> String {
    #if DEBUG
    let verbose = true
    #else
    let verbose = false
    #endif

    struct E: Error, LocalizedError {
        var errorDescription: String? {
            "Failed to parse answer."
        }
    }

    let task = Task {
        try withReadableThrowingPython {
            let langchain = try Python.attemptImport("langchain")
            let LLMMathChain = langchain.LLMMathChain
            let llm = try LangChainChatModel.DynamicChatOpenAI(temperature: 0)
            let llmMath = LLMMathChain.from_llm(llm, verbose: verbose)
            let result = try llmMath.run.throwing.dynamicallyCall(withArguments: problem)
            let answer = String(result)
            if let answer { return answer }

            throw E()
        }
    }

    return try await task.value
}