code: def path(self, which=None):
          
          if which in ('download_html',):
              return '{0}/{1}'.format(
                  super(ArfReport, self).path(which='self'),
                  which
              )
          return super(ArfReport, self).path(which)
docs: Extend ``nailgun.entity_mixins.Entity.path``.
          The format of the returned path depends on the value of ``which``:
  
          download_html
              /api/compliance/arf_reports/:id/download_html
  
          Otherwise, call ``super``.