```ruby
require 'sax-machine'

require 'green-button-data/core_ext'
require 'green-button-data/dst'
require 'green-button-data/enumerations'
require 'green-button-data/utilities'
require 'green-button-data/parser'
require 'green-button-data/rational_number'
require 'green-button-data/parser/interval'
require 'green-button-data/parser/interval_reading'
require 'green-button-data/parser/authorization'
require 'green-button-data/parser/application_information'
require 'green-button-data/parser/service_category'
require 'green-button-data/parser/local_time_parameter'

module GreenButtonData
end
```

Add ReadingType class to requires
user
```ruby
require 'sax-machine'

require 'green-button-data/core_ext'
require 'green-button-data/dst'
require 'green-button-data/enumerations'
require 'green-button-data/utilities'
require 'green-button-data/parser'
require 'green-button-data/rational_number'
require 'green-button-data/parser/interval'
require 'green-button-data/parser/interval_reading'
require 'green-button-data/parser/authorization'
require 'green-button-data/parser/application_information'
require 'green-button-data/parser/service_category'
require 'green-button-data/parser/local_time_parameters'
require 'green-button-data/parser/reading_type'

module GreenButtonData
end
```
assistant