            doc/example2.md fenced blocks
-----------------------------------------------------
block     line  test          TEXT or directive
type    number  role          quoted and one per line
-----------------------------------------------------
python       9  code
            14  output
python      20  skip-code     "Python 3.7"
            26  skip-output
            31  --
python      37  code
python      44  code
            51  output
yaml        59  --
text        67  --
py          75  session
python      87  code
            94  output
py         102  skip-session  "LAST"
-----------------------------------------------------
5 test cases.
1 skipped code blocks.
1 skipped interactive session blocks.
1 code blocks with no output block.

  skip pattern matches (blank means no match)
------------------------------------------------
skip pattern  matching code block line number(s)
------------------------------------------------
Python 3.7    20
LAST          102
------------------------------------------------
