old_contents: 
  
  class Info:
      """
      >>> info = Info()
      >>> info.title = "ABC Style"
      >>> print(info.title)
      ABC Style
      >>> info.add_category('author-date')
      >>> print(info.categories[0])
      author-date
      """
      def __init__(self, title=None, id=None, updated=None):
          self.title = title
          self.id = id
          self.updated = updated
          self.categories = []
  
      def add_category(self, category):
          self.categories.append(category)
  
  
  class Option:
      """
      >>> option = Option('et-al-min', '4')
      >>> print(option.value)
      4
      """
      def __init__(self, name, value):
          self.name = name
          self.value = value
  
  
  class Context:
      """
      >>> context = Context()
      >>> len(context.options)
      0
      >>> context.add_option('et-al-min', 5)
      >>> len(context.options)
      1
      """
      def __init__(self):
          self.options = []
          self.sort = []
          self.layout = []
  
      def add_option(self, name, value):
          self.options.append(Option(name, value))
  
  
  class Citation(Context):
      """
      >>> citation = Citation()
      >>> len(citation.options)
      0
      >>> citation.add_option('et-al-min', 5)
      >>> len(citation.options)
      1
      """
      pass
  
  
  
  class Bibliography(Context):
      """
      >>> bib = Bibliography()
      >>> len(bib.options)
      0
      >>> bib.add_option('et-al-min', 5)
      >>> len(bib.options)
      1
      """
      pass
  
  
  
  class Template:
      pass
  
  
  
  class Macro(Template):
      pass
  
  
  class Style:
      """
      >>> style = Style()
      """
      def __init__(self):
          self.info = Info()
          self.macros = []
          self.citation = Citation()
          self.bibliography = Bibliography()
  
  
  
new_contents: 
  
  class Info:
      """
      >>> info = Info()
      >>> info.title = "ABC Style"
      >>> print(info.title)
      ABC Style
      >>> info.add_category('author-date')
      >>> print(info.categories[0])
      author-date
      """
      def __init__(self, title=None, id=None, updated=None):
          self.title = title
          self.id = id
          self.updated = updated
          self.categories = []
  
      def add_category(self, category):
          self.categories.append(category)
  
  
  class Option:
      """
      >>> option = Option('et-al-min', '4')
      >>> print(option.value)
      4
      """
      def __init__(self, name, value):
          self.name = name
          self.value = value
  
  
  class Context:
      """
      >>> context = Context()
      >>> len(context.options)
      0
      >>> context.add_option('et-al-min', 5)
      >>> len(context.options)
      1
      """
      def __init__(self):
          self.options = []
          self.sort = []
          self.layout = []
  
      def add_option(self, name, value):
          self.options.append(Option(name, value))
  
  
  class Citation(Context):
      """
      >>> citation = Citation()
      >>> len(citation.options)
      0
      >>> citation.add_option('et-al-min', 5)
      >>> len(citation.options)
      1
      """
      pass
  
  
  
  class Bibliography(Context):
      """
      >>> bib = Bibliography()
      >>> len(bib.options)
      0
      >>> bib.add_option('et-al-min', 5)
      >>> len(bib.options)
      1
      """
      pass
  
  
  
  class Template:
      pass
  
  
  
  class Macro(Template):
      pass
  
  
  class Style:
      """
      >>> style = Style()
      >>> print(style.info)
      None
      """
      def __init__(self, info=None, macros=[], 
                   citation=None, bibliography=None):
          self.info = info
          self.macros = macros
          self.citation = citation
          self.bibliography = bibliography
  
  
  
subject: change init on Style