def add_line_with_subsequent_indent(self, line, indent=4):
        """Add line of text and wrap such that subsequent lines are indented
        by `indent` spaces.
        """
        if isinstance(line, (list, tuple)):
            line = ''.join(line)
        line = line.strip()
        width = self.textwidth-self.indent-indent
        wrapped_lines = textwrap.wrap(line[indent:], width=width)
        for i in range(len(wrapped_lines)):
            if wrapped_lines[i] != '':
                wrapped_lines[i] = indent * ' ' + wrapped_lines[i]
        self.pieces.append(line[:indent] + '\n'.join(wrapped_lines)[indent:] + '  \n')
Add line of text and wrap such that subsequent lines are indented
        by `indent` spaces.