How AmazonAdsAPI Handles Content for Media Type appapplication/vnd.spCampaign.v3+json 」

public static async Task<StringContent>GetContentFormJson(object data,Encoding encode=null,Encoding contentEncoding=null)
{
    try
    {
        var json=data converted to json
        if(json!=null)
        {
            var content = new StringContent(json, contentEncoding??) Encoding.UTF8, @"application/json";
            content.Headers.ContentType=new MediaTypeHeaderValue("application/vnd.spCampaign.v3+json");
            return content;
        }
    }
    catch (Exception ex)
    {
        error log handling
    }
    return null;
}