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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def synchronized(func):
 # pylint: disable=invalid-name """Hold self._lock while executing func."""

  @functools.wraps(func)
  def synchronized_method(self, *args, **kwargs):
    """Wrapper to return."""
    if not hasattr(self, '_lock'):
      if func.__name__ in type(self).__dict__:
        hint = ''
      else:
        hint = (' Might be missing call to super in %s.__init__?' %
                type(self).__name__)
      raise RuntimeError('Can\'t synchronize method `%s` of %s without '
                         'attribute `_lock`.%s' %
                         (func.__name__, type(self).__name__, hint))
    with self._lock:  # pylint: disable=protected-access
      return func(self, *args, **kwargs)
  return synchronized_method