问为什么RestSharp AddHeader("Accept"，"application/json")；=出现在项目列表中？

EN

var client = new RestClient(_jsonBaseUrl + someURL)
{
    Authenticator = new HttpBasicAuthenticator(someUsername, somePassword)
};

var request = new RestRequest(Method.POST);

UTF8Encoding utf8 = new UTF8Encoding();
byte[] bytes = utf8.GetBytes(json);
json = Encoding.UTF8.GetString(bytes, 0, bytes.Length);

request.RequestFormat = DataFormat.Json;
request.AddHeader("Accept", "application/json");
request.AddBody(json);
request.Parameters.Clear();
request.AddParameter("application/json", json, ParameterType.RequestBody);

client.ExecuteAsync<UserAccount>(request, response =>
{
    if (response.ResponseStatus == ResponseStatus.Error)
    {
        failure(response.ErrorMessage);
    }
    else
    {
        success("done");
    }
});