+require 'date'
+require 'active_support/core_ext/time/behavior'
+require 'active_support/core_ext/time/zones'
+require 'active_support/core_ext/date_time/calculations'
+require 'active_support/core_ext/date_time/conversions'
+
+class DateTime
+ include ActiveSupport::CoreExtensions::Time::Behavior
+ include ActiveSupport::CoreExtensions::Time::Zones
+ include ActiveSupport::CoreExtensions::DateTime::Calculations
+ include ActiveSupport::CoreExtensions::DateTime::Conversions
+end