old_contents: from case_conversion import (
      camelcase, pascalcase, snakecase, dashcase, kebabcase, spinalcase,
      constcase, dotcase, separate_words, slashcase, backslashcase)
  
new_contents: from __future__ import absolute_import
  
  from .case_conversion import (
      camelcase, pascalcase, snakecase, dashcase, kebabcase, spinalcase,
      constcase, dotcase, separate_words, slashcase, backslashcase)
  
subject: Fix import errors from implicit-relative imports.