new_contents: #!/usr/bin/env python
  
  """
  A utility to fix PLY-generated lex and yacc tables to be Python 2 and
  3 compatible.
  """
  
  import os
  
  for root, dirs, files in os.walk(os.path.join(os.path.dirname(__file__), '..')):
      for fname in files:
          if not (fname.endswith('lextab.py') or fname.endswith('parsetab.py')):
              continue
  
          path = os.path.join(root, fname)
          with open(path, 'rb') as fd:
              lines = fd.readlines()
  
          with open(path, 'wb') as fd:
              fd.write("# Licensed under a 3-clause BSD style license - see LICENSE.rst\n")
              fd.write("from __future__ import (absolute_import, division, print_function, unicode_literals)\n")
              fd.write('\n')
  
              lines = [x.replace("u'", "'").replace('u"', '"') for x in lines]
              lines = [x for x in lines if not (fname in x and x[0] == '#')]
  
              fd.write(''.join(lines))
  
subject: move clean_parse_tables.py from astropy to astropy-tools