simple but unusual system allows for a dramatic savings in Python
overhead for the construction and processing of orm :class:`.Query`
objects, from query construction up through rendering of a string
SQL statement.
fixes#3054
directly into the unit of work's facility for emitting INSERT
and UPDATE statements has been created. When used correctly,
this expert-oriented system can allow ORM-mappings to be used
to generate bulk insert and update statements batched into
executemany groups, allowing the statements to proceed at
speeds that rival direct use of the Core.
fixes#3100
Patrick