'Return one line element of a line_block.'

def line_block_line(self, match, lineno):

    (indented, indent, line_offset, blank_finish) = self.state_machine.get_first_known_indented(match.end(), until_blank=1)
    text = u'\n'.join(indented)
    (text_nodes, messages) = self.inline_text(text, lineno)
    line = nodes.line(text, '', *text_nodes)
    if (match.string.rstrip() != '|'):
        line.indent = (len(match.group(1)) - 1)
    return (line, messages, blank_finish)
