[DB-SIG] Escaping Placeholders

[Peter L. Buschman]

I know there must be an obvious answer to this question, but what is the 
standard mechanism
for escaping placeholders in dbapi execute method calls?

Eg., when using the qmark paramstyle and I want to include a literal 
question-mark, do I use \?, '?', ??,
or something else entirely? Ditto for format, named, etc., in any 
situations where literal text in the query
might be mistaken for a placeholder.

--PLB