Getting user's groups
Add the namespace:
using EleWise.ELMA.Security.Managers
Below is a script which gets all the groups a specific user (context.Executor) is included in.
var groups = UserGroupManager.Instance.GetGroupsByUser(context.Executor.Id).Select(id => UserGroupManager.Instance.Load(id)); //get all the groups of the user
foreach(var group in groups.ToList())
{
Console.WriteLine(group.Name); //display the name in the console
}