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: items_controller.rb
    path of file: ./repos/ekylibre/app/controllers/backend/bank_reconciliation
    
    the code of the file until where you have to start completion: module Backend
  module BankReconciliation
    # Handles bank reconciliation.
    class ItemsController < Backend::BaseController
 
    
      def reconciliate
        return unless cash = find_cash
        return unless @bank_statements = find_bank_statements(cash)

        cash = cash.first if cash.is_a?(Array)
        set_period!
        @items = cash.unpointed_journal_entry_items.between(@period_start, @period_end)
        @bank_statements.each do |bank_statement|
          reconciliate_one(bank_statement)
        end
        @items_grouped_by_date = group_by_date(@items)
        @options = build_form_options
        t3e cash: cash.name, started_on: @period_start.l, stopped_on: @period_end.l
      end