AzureDevOpsAuthenticationError: The requested resource requires user authentication: https://dev.azure.com/myorg/_apis

I followed the sample code:

        credentials = BasicAuthentication(username=user, password=pat)
        self.connection = Connection(base_url="https://dev.azure.com/myorg/", creds=credentials)
        testClient = self.connection.clients.get_core_client()

But I get exception. Did I miss something?

   testClient = self.connection.clients.get_core_client()
  File "/Users/runner/hostedtoolcache/Python/3.10.0/x64/lib/python3.10/site-packages/azure/devops/released/client_factory.py", line 44, in get_core_client
    return self._connection.get_client('azure.devops.released.core.core_client.CoreClient')
  File "/Users/runner/hostedtoolcache/Python/3.10.0/x64/lib/python3.10/site-packages/azure/devops/connection.py", line 45, in get_client
    self._client_cache[client_type] = self._get_client_instance(client_class)
  File "/Users/runner/hostedtoolcache/Python/3.10.0/x64/lib/python3.10/site-packages/azure/devops/connection.py", line 58, in _get_client_instance
    url = self._get_url_for_client_instance(client_class)
  File "/Users/runner/hostedtoolcache/Python/3.10.0/x64/lib/python3.10/site-packages/azure/devops/connection.py", line 70, in _get_url_for_client_instance
    resource_areas = self._get_resource_areas()
  File "/Users/runner/hostedtoolcache/Python/3.10.0/x64/lib/python3.10/site-packages/azure/devops/connection.py", line 120, in _get_resource_areas
    self._resource_areas = location_client.get_resource_areas()
  File "/Users/runner/hostedtoolcache/Python/3.10.0/x64/lib/python3.10/site-packages/azure/devops/v5_1/location/location_client.py", line 104, in get_resource_areas
    response = self._send(http_method='GET',
  File "/Users/runner/hostedtoolcache/Python/3.10.0/x64/lib/python3.10/site-packages/azure/devops/client.py", line 74, in _send
    request = self._create_request_message(http_method=http_method,
  File "/Users/runner/hostedtoolcache/Python/3.10.0/x64/lib/python3.10/site-packages/azure/devops/client.py", line 119, in _create_request_message
    location = self._get_organization_resource_location(location_id)
  File "/Users/runner/hostedtoolcache/Python/3.10.0/x64/lib/python3.10/site-packages/azure/devops/client.py", line 160, in _get_organization_resource_location
    return self._get_resource_location(self.normalized_url, location_id)
  File "/Users/runner/hostedtoolcache/Python/3.10.0/x64/lib/python3.10/site-packages/azure/devops/client.py", line 172, in _get_resource_location
    Client._locations_cache[url] = self._get_resource_locations(url, all_host_types=False)
  File "/Users/runner/hostedtoolcache/Python/3.10.0/x64/lib/python3.10/site-packages/azure/devops/client.py", line 208, in _get_resource_locations
    response = self._send_request(request, headers=headers)
  File "/Users/runner/hostedtoolcache/Python/3.10.0/x64/lib/python3.10/site-packages/azure/devops/client.py", line 68, in _send_request
    self._handle_error(request, response)
  File "/Users/runner/hostedtoolcache/Python/3.10.0/x64/lib/python3.10/site-packages/azure/devops/client.py", line 290, in _handle_error
    raise AzureDevOpsAuthenticationError(full_message_format.format(error_message=error_message,

Start with the Connection(...) and BasicAuthentication sample, then trace get_core_client through azure/devops/connection.py and azure/devops/client.py to the resource-area request shown in the stack trace. Reproduce the authentication failure and identify the missing configuration or endpoint detail; done means the sample authenticates successfully or the required correction is documented.