old_contents: let defaults = getDefaults();
  
  function getDefaults() {
    return {
      baseUrl: null,
      breaks: false,
      gfm: true,
      headerIds: true,
      headerPrefix: '',
      highlight: null,
      langPrefix: 'language-',
      mangle: true,
      pedantic: false,
      renderer: null,
      sanitize: false,
      sanitizer: null,
      silent: false,
      smartLists: false,
      smartypants: false,
      xhtml: false
    };
  }
  
  function changeDefaults(newDefaults) {
    defaults = newDefaults;
  }
  
  module.exports = {
    defaults,
    getDefaults,
    changeDefaults
  };
  
new_contents: function getDefaults() {
    return {
      baseUrl: null,
      breaks: false,
      gfm: true,
      headerIds: true,
      headerPrefix: '',
      highlight: null,
      langPrefix: 'language-',
      mangle: true,
      pedantic: false,
      renderer: null,
      sanitize: false,
      sanitizer: null,
      silent: false,
      smartLists: false,
      smartypants: false,
      xhtml: false
    };
  }
  
  function changeDefaults(newDefaults) {
    module.exports.defaults = newDefaults;
  }
  
  module.exports = {
    defaults: getDefaults(),
    getDefaults,
    changeDefaults
  };
  
subject: fix changing global defaults