code: def get_build_info(self):
          
          # Retrieve build by revision
          if self.revision:
              th = treeherder.Treeherder(
                  APPLICATIONS_TO_FTP_DIRECTORY.get(self.application, self.application),
                  self.branch,
                  self.platform)
              builds = th.query_builds_by_revision(
                  self.revision, job_type_name='Build', debug_build=self.debug_build)
  
              if not builds:
                  raise errors.NotFoundError('No builds have been found for revision', self.revision)
  
              # Extract timestamp from each build folder
              self.builds = [build.rsplit('/', 2)[1] for build in builds]
              self.show_matching_builds(self.builds)
  
              # There is only a single build
              self.build_index = 0
              self.logger.info('Selected build: %s' % self.builds[self.build_index])
  
              return
  
          # Internally we access builds via index
          if self.build_number is not None:
              self.build_index = int(self.build_number) - 1
          else:
              self.build_index = None
  
          if self.date is not None:
              try:
                  # date is provided in the format 2013-07-23
                  self.date = datetime.strptime(self.date, '%Y-%m-%d')
              except Exception:
                  try:
                      # date is provided as a unix timestamp
                      datetime.fromtimestamp(float(self.date))
                      self.timestamp = self.date
                  except Exception:
                      raise ValueError('%s is not a valid date' % self.date)
  
          # For localized builds we do not have to retrieve the list of builds
          # because only the last build is available
          if not self.locale_build:
              self.builds, self.build_index = self.get_build_info_for_index(
                  self.build_index)
              # Always force a timestamp prefix in the filename
              self.timestamp = self.builds[self.build_index]
docs: Define additional build information.