Trying to return list of events on a calendar, but not getting any thing returned to the view

gistfile1.txt

#event_controller.rb
class EventsController < ApplicationController
  def index
    @events = Event.all
    @events_by_date = @events.group_by(&:date)
  end
end

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# index.html.erb
<%= calendar do |date| %>
  <%= date.day %>
  <% if @events_by_date[date] %>
    <ul>
      <% @events_by_date[date].each do |event| %>
        <li><%= event.title %></li>
      <% end %>
    </ul>
  <% end %>
<% end %>