'Set the peek.  This method is used by various subclasses of Text.'

def set_peek(self, dataset, line_count=None, is_multi_byte=False, WIDTH=256, skipchars=None, line_wrap=True):

    if (not dataset.dataset.purged):
        dataset.peek = get_file_peek(dataset.file_name, is_multi_byte=is_multi_byte, WIDTH=WIDTH, skipchars=skipchars, line_wrap=line_wrap)
        if (line_count is None):
            if dataset.metadata.data_lines:
                dataset.blurb = ('%s    %s' % (util.commaify(str(dataset.metadata.data_lines)), inflector.cond_plural(dataset.metadata.data_lines, self.line_class)))
            elif (int(dataset.get_size()) <= 1048576):
                lc = self.count_data_lines(dataset)
                dataset.metadata.data_lines = lc
                dataset.blurb = ('%s    %s' % (util.commaify(str(lc)), inflector.cond_plural(lc, self.line_class)))
            else:
                est_lines = self.estimate_file_lines(dataset)
                dataset.blurb = ('~%s    %s' % (util.commaify(util.roundify(str(est_lines))), inflector.cond_plural(est_lines, self.line_class)))
        else:
            dataset.blurb = ('%s    %s' % (util.commaify(str(line_count)), inflector.cond_plural(line_count, self.line_class)))
    else:
        dataset.peek = 'file    does    not    exist'
        dataset.blurb = 'file    purged    from    disk'
