Failed to import the solution after adding UDF

@Jon_Herke @Dan_Barkus I added the UDF of string splitting in my ExprFunctions.hpp file
just before the ArrayAccum

inline ListAccum string_split (string str, string delimiter) {

ListAccum<string> newList;

size_t pos = 0;

std::string token;

while ((pos = str.find(delimiter)) != std::string::npos) {

  token = str.substr(0, pos);

  newList += token;

  str.erase(0, pos + delimiter.length());

}

newList += str;

return newList;

}

    

  inline ArrayAccum<SumAccum<double>> unit_ArrayAccum (int len) {

      gvector<int64_t> dim;

      dim.push_back(len);

      ArrayAccum<SumAccum<double>> yArray(dim);

      for (uint32_t i=0; i < yArray.data_.size(); i++){

        yArray.data_[i] = 1;

    }

      return yArray;

  }

and after I converted to tar.gz and then after importing the solution i am getting this error Failed to import key-value store.
image

Can you please guide me here what I am doing wrong here