Delete

        Deletes directory and drops the file name from dictionary.  File on
        file system removed on disk.

def delete(self):
        """ Delete

        Deletes directory and drops the file name from dictionary.  File on
        file system removed on disk.
        """

        directory = self._directory()
        assert isinstance(directory, Directory)

        realPath = self.realPath
        assert (os.path.exists(realPath))
        os.remove(realPath)

        directory._fileDeleted(self)