You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: group_assignments_controller.rb
    path of file: ./repos/classroom/app/controllers
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

    
  def edit; end

  def update
    result = Assignment::Editor.perform(assignment: @group_assignment, options: update_group_assignment_params.to_h)
    if result.success?
      flash[:success] = "Assignment \"#{@group_assignment.title}\" is being updated"
      redirect_to organization_group_assignment_path(@organization, @group_assignment)
    else
      @group_assignment.reload if @group_assignment.slug.blank?
      render :edit
    end
  end