Location:
http://docs.python.org/devguide/compiler.html#parse-trees

- To tie all of this example, consider the rule for ‘while’:

Probably meant to be: To tie all of this together with an example, ...

- The node representing this will have TYPE(node) == while_stmt and the number of children can be 4 or 7 depending on if there is an ‘else’ statement.

s/if/whether/g is slightly better English imo

- To access what should be the first ‘:’ and require it be an actual ‘:’ token, (REQ(CHILD(node, 2), COLON)`.

Understandable with some effort on the reader's part, but it's not very well worded.

Notice also the closing backtick: markup typo.