anchor.diff:  <% @booking_postal_codes.each do |booking_postal_code| %>
     <tr>
       <td><%= booking_postal_code.booking_postal_codes_id %></td>
  -    <td><%= booking_postal_code.booking_group_id%></td>
  +    <td><%= booking_postal_code.booking_group.name%></td>
       <td><%= link_to 'Show', admin_booking_postal_code_path(booking_postal_code) %></td>
       <td><%= link_to 'Edit', edit_admin_booking_postal_code_path(booking_postal_code) %></td>
       <td><%= link_to 'Destroy', admin_booking_postal_code_path(booking_postal_code), method: :delete, data: { confirm: 'Are you sure?' } %></td>
  
positive.code: <%= button_link_to 'New Booking postal code', new_admin_booking_postal_code_path %>
  
  <h1>Listing Booking Postal Codes</h1>
  
negative.code: <table>
    <tr>
      <th>Name</th>
      <th>Booking group name</th>
      <th></th>
      <th></th>
      <th></th>
  