>>> import albatross
>>> ctx = albatross.SimpleContext('.')
>>> albatross.Template(ctx, '<magic>', '''
... <al-macro name="double">
...  1. <al-usearg>
...  2. <al-usearg>
... </al-macro>
... ''').to_html(ctx)
>>> ctx.flush_content()
>>> albatross.Template(ctx, '<magic>', '''
... <al-expand name="double">
...  spam
... </al-expand>''').to_html(ctx)
>>> ctx.flush_content()
1. spam
2. spam
