Issue #27744:

* Release msg.msg_iov memory block.
* Release memory on PyMem_Malloc(controllen) failure

Issue #27744:

* PEP 7: add {...} around if blocks
* assign variables and then check their value in if() to make the code easier
  to read and to debug.

(Patch by Duane Griffin.  Reviewed and approved by Stefan Behnel.)

Patch by Roger Serwy, updated by Bayard Randel.

Patch by Roger Serwy, updated by Bayard Randel.

Patch by wim glenn.

Patch adapted from https://github.com/ghaering/pysqlite/commit/9b79188edbc50faa24dc178afe24a10454f3fcad

Ivan Levkivskyi (3.5 version)

Ivan Levkivskyi (3.6 version)