def add_group_users(user_ids)
      raise 'Attempted to add a user to a non-group channel!' unless group?

      user_ids = [user_ids] unless user_ids.is_a? Array
      user_ids.each do |user_id|
        API::Channel.add_group_user(@bot.token, @id, user_id.resolve_id)
      end
      self
    end
def add_group_users(user_ids)
      raise 'Attempted to add a user to a non-group channel!' unless group?

      user_ids = [user_ids] unless user_ids.is_a? Array
      user_ids.each do |user_id|
        API::Channel.add_group_user(@bot.token, @id, user_id.resolve_id)
      end
      self
    end
Adds a user to a group channel.
 @param user_ids [Array<#resolve_id>, #resolve_id] User ID or array of user IDs to add to the group channel.
 @return [Channel] the group channel.