public static String signatureToString(PySignature signature) {
    return signature.getFunctionName() + "\t" + StringUtil.join(arguments(signature), "\t") +
           (signature.getReturnType() != null
            ? "\t" + StringUtil.join(
             signature.getReturnType().getTypesList().stream().map(s -> RETURN_TYPE + ":" + s).collect(Collectors.toList()), "\t") : "");
  }
public static String signatureToString(PySignature signature)