new_contents: import json
  import unittest
  
  from ..exceptions import (
      JSONRPCError,
      JSONRPCInternalError,
      JSONRPCInvalidParams,
      JSONRPCInvalidRequest,
      JSONRPCMethodNotFound,
      JSONRPCParseError,
      JSONRPCServerError,
  )
  
  
  class TestJSONRPCError(unittest.TestCase):
      def setUp(self):
          self.error_params = {
              "code": 0,
              "message": "",
          }
  
      def test_correct_init(self):
          """ Test object is created."""
          JSONRPCError(**self.error_params)
  
      def test_validation_incorrect_no_parameters(self):
          with self.assertRaises(ValueError):
              JSONRPCError()
  
      def test_code_validation_int(self):
          self.error_params.update({"code": 32000})
          JSONRPCError(**self.error_params)
  
      def test_code_validation_no_code(self):
          del self.error_params["code"]
          with self.assertRaises(ValueError):
              JSONRPCError(**self.error_params)
  
      def test_code_validation_str(self):
          self.error_params.update({"code": "0"})
          with self.assertRaises(ValueError):
              JSONRPCError(**self.error_params)
  
      def test_message_validation_str(self):
          self.error_params.update({"message": ""})
          JSONRPCError(**self.error_params)
  
      def test_message_validation_none(self):
          del self.error_params["message"]
          with self.assertRaises(ValueError):
              JSONRPCError(**self.error_params)
  
      def test_message_validation_int(self):
          self.error_params.update({"message": 0})
          with self.assertRaises(ValueError):
              JSONRPCError(**self.error_params)
  
      def test_data_validation_none(self):
          self.error_params.update({"data": None})
          JSONRPCError(**self.error_params)
  
      def test_data_validation(self):
          self.error_params.update({"data": {}})
          JSONRPCError(**self.error_params)
  
          self.error_params.update({"data": ""})
          JSONRPCError(**self.error_params)
  
      def test_from_json(self):
          str_json = json.dumps({
              "code": 0,
              "message": "",
              "data": {},
          })
  
          request = JSONRPCError.from_json(str_json)
          self.assertTrue(isinstance(request, JSONRPCError))
          self.assertEqual(request.code, 0)
          self.assertEqual(request.message, "")
          self.assertEqual(request.data, {})
  
  
  class TestJSONRPCParseError(unittest.TestCase):
      def test_code_message(self):
          error = JSONRPCParseError()
          self.assertEqual(error.code, -32700)
          self.assertEqual(error.message, "Parse error")
          self.assertEqual(error.data, None)
  
  
  class TestJSONRPCServerError(unittest.TestCase):
      def test_code_message(self):
          error = JSONRPCServerError()
          self.assertEqual(error.code, -32000)
          self.assertEqual(error.message, "Server error")
          self.assertEqual(error.data, None)
  
  
  class TestJSONRPCInternalError(unittest.TestCase):
      def test_code_message(self):
          error = JSONRPCInternalError()
          self.assertEqual(error.code, -32603)
          self.assertEqual(error.message, "Internal error")
          self.assertEqual(error.data, None)
  
  
  class TestJSONRPCInvalidParams(unittest.TestCase):
      def test_code_message(self):
          error = JSONRPCInvalidParams()
          self.assertEqual(error.code, -32602)
          self.assertEqual(error.message, "Invalid params")
          self.assertEqual(error.data, None)
  
  
  class TestJSONRPCInvalidRequest(unittest.TestCase):
      def test_code_message(self):
          error = JSONRPCInvalidRequest()
          self.assertEqual(error.code, -32600)
          self.assertEqual(error.message, "Invalid Request")
          self.assertEqual(error.data, None)
  
  
  class TestJSONRPCMethodNotFound(unittest.TestCase):
      def test_code_message(self):
          error = JSONRPCMethodNotFound()
          self.assertEqual(error.code, -32601)
          self.assertEqual(error.message, "Method not found")
          self.assertEqual(error.data, None)
  
subject: move tests for json rpc errors to another file. They could be used in both standards