old_contents: #!/usr/bin/env python
  # Copyright 2014 Marc-Antoine Ruel. All rights reserved.
  # Use of this source code is governed under the Apache License, Version 2.0
  # that can be found in the LICENSE file.
  
  """Installs git pre-commit hook on the repository one directory above."""
  
  import os
  import shutil
  import subprocess
  import sys
  
  
  THIS_DIR = os.path.dirname(os.path.abspath(__file__))
  
  
  def main():
    try:
      parent = os.path.dirname(THIS_DIR)
      git_dir = subprocess.check_output(
          ['git', 'rev-parse', '--git-dir'],
          cwd=parent).strip()
      git_dir = os.path.normpath(os.path.join(parent, git_dir))
    except subprocess.CalledProcessError:
      print >> sys.stderr, 'Failed to find parent git repository root'
      return 1
  
    git_hook_dir = os.path.join(git_dir, 'hooks')
    precommit_dest = os.path.join(git_hook_dir, 'pre-commit')
    if os.path.isfile(precommit_test):
      # Better be safe than sorry.
      print >> sys.stderr, '%s already exist, aborting' % precommit_dest
      return 1
  
    if sys.platform == 'win32':
      # This means it'll get stale on Windows.
      shutil.copyfile(os.path.join(THIS_DIR, 'pre-commit'), precommit_dest)
    else:
      relpath = os.path.relpath(THIS_DIR, git_hook_dir)
      os.symlink(os.path.join(relpath, 'pre-commit'), precommit_dest)
    print('Installed %s' % precommit_dest)
    return 0
  
  
  if __name__ == '__main__':
    sys.exit(main())
  
new_contents: #!/usr/bin/env python
  # Copyright 2014 Marc-Antoine Ruel. All rights reserved.
  # Use of this source code is governed under the Apache License, Version 2.0
  # that can be found in the LICENSE file.
  
  """Installs git pre-commit hook on the repository one directory above."""
  
  import os
  import shutil
  import subprocess
  import sys
  
  
  THIS_DIR = os.path.dirname(os.path.abspath(__file__))
  
  
  def main():
    try:
      parent = os.path.dirname(THIS_DIR)
      git_dir = subprocess.check_output(
          ['git', 'rev-parse', '--git-dir'],
          cwd=parent).strip()
      git_dir = os.path.normpath(os.path.join(parent, git_dir))
    except subprocess.CalledProcessError:
      print >> sys.stderr, 'Failed to find parent git repository root'
      return 1
  
    git_hook_dir = os.path.join(git_dir, 'hooks')
    precommit_dest = os.path.join(git_hook_dir, 'pre-commit')
    if os.path.isfile(precommit_dest):
      # Better be safe than sorry.
      print >> sys.stderr, '%s already exist, aborting' % precommit_dest
      return 1
  
    if sys.platform == 'win32':
      # This means it'll get stale on Windows.
      shutil.copyfile(os.path.join(THIS_DIR, 'pre-commit'), precommit_dest)
    else:
      relpath = os.path.relpath(THIS_DIR, git_hook_dir)
      os.symlink(os.path.join(relpath, 'pre-commit'), precommit_dest)
    print('Installed %s' % precommit_dest)
    return 0
  
  
  if __name__ == '__main__':
    sys.exit(main())
  
subject: Fix typo