Set the previously saved indentation level.

def set_indent(TokenClass, implicit=False):
    """Set the previously saved indentation level."""
    def callback(lexer, match, context):
        text = match.group()
        if context.indent < context.next_indent:
            context.indent_stack.append(context.indent)
            context.indent = context.next_indent
        if not implicit:
            context.next_indent += len(text)
        yield match.start(), TokenClass, text
        context.pos = match.end()
    return callback