string ret;
  for (int64_t i = 0; i < num_elts; ++i) {
    if (i > 0) strings::StrAppend(&ret, ", ");
    strings::StrAppend(&ret, array[i]);
  }
  return ret;
}

string PrintTensor(const TensorProto& tensor_proto);

string PrintTensorProto(const TensorProto& proto);

string PrintAttrValue(StringPiece, const AttrValue& attr_value);

bool IsEmptyList(const AttrValue::ListValue& list);