python Timer contextmanager

class Timer:
    """
    A ``Timer`` ContextManager to simplify timing sections of code.
    """
    def __init__(self, name=None, logger=None, log_level=logging.DEBUG):
        """
        Constructs a ``Timer``.

        Parameters
        ----------
        name : str
            An optional name for the timer, to be used for logging messages.
        logger : logging.Logger
            An optional logger for logging the elapsed time.
        log_level : logging.LEVEL
            An optional logging level (enumeration on logging module).
        """
        self._name = name
        self._logger = logger
        self._log_level = log_level

    def __enter__(self):
        self.start = time.time()
        return self

    def __exit__(self, *args):
        self.end = time.time()
        self.interval = self.end - self.start
        if self._logger:
            self._logger.log(self._log_level, '{name} took {time} seconds.'.format(
                name=self._name,
                time=self.interval
            ))