underlying buffer (previously this was only done when deallocating the
memoryview), and gain support for the context management protocol.

a memoryview object.

frombytes() and tobytes(), respectively, to avoid confusion.  Furthermore,
array.frombytes(), array.extend() as well as the array.array()
constructor now accept bytearray objects.  Patch by Thomas Jollans.

svn+ssh://pythondev@svn.python.org/python/trunk

........
  r77727 | ezio.melotti | 2010-01-24 18:58:36 +0200 (Sun, 24 Jan 2010) | 1 line

  use assert[Not]IsInstance where appropriate
........

Also fix len() to return number of items rather than length in bytes.

I'm sorry it was not possible for me to work on this without reindenting
a bit some stuff around. The indentation in memoryobject.c is a mess,
I'll open a separate bug for it.

(together with a bit of reindenting)

Reviewer: Antoine Pitrou #3827

Reviewed by Benjamin Peterson.

Fixed memoryview constructor. It allowed arbitrary keyword arguments. The bug was found by mykhal from #python. I've also added a small test case in the new test_memoryview.py