old_contents: from __future__ import unicode_literals
  
  from .impl import verify_spec_name
  from .impl import get_spec_plugin_list
  from .impl import Spec
  from .rules import SpecParsingError
  
  __all__ = ['get_spec_plugin_list', 'SpecParsingError', 'verify_spec_name',
             'Spec']
  
new_contents: from __future__ import unicode_literals
  
  from .impl import verify_spec_name
  from .impl import get_spec_plugin_list
  from .impl import Spec
  from .plugins.rules import SpecParsingError
  
  __all__ = ['get_spec_plugin_list', 'SpecParsingError', 'verify_spec_name',
             'Spec']
  
subject: Fix type causing import error.