'Delete the object.
This implementation creates a tombstone file using the given
timestamp, and removes any older versions of the object file. Any
file that has an older timestamp than timestamp will be deleted.
.. note::
An implementation is free to use or ignore the timestamp
parameter.
:param timestamp: timestamp to compare with each file
:raises DiskFileError: this implementation will raise the same
errors as the `create()` method.'

def delete(self, timestamp):

    timestamp = Timestamp(timestamp)
    with self.create() as deleter:
        deleter._extension = '.ts'
        deleter.put({'X-Timestamp': timestamp.internal})
