The namedtuple example is wrong. The constructor requires all of the parameters, and an attribute cannot be set:

    >>> from collections import namedtuple
    >>> LightObject = namedtuple('LightObject', ['shortname', 'otherprop'])
    >>> m = LightObject()
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
    TypeError: __new__() takes exactly 3 arguments (1 given)
    >>> m = LightObject("first", "second")
    >>> m.shortname
    'first'
    >>> m.shortname = 'athing'
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
    AttributeError: can't set attribute

Also, bare try/excepts as in:

    try:
      # get API data
      data = db.find(id='foo') # may raise exception
    except:
      # log the failure and bail out
      log.warn("Could not retrieve FOO")
      return

are really bad. The failure might be caused by a ^C or MemoryError, or even a SystemExit, should db.find() desire to do that.

Instead, qualify it by catching Exception:

    try:
      # get API data
      data = db.find(id='foo') # may raise exception
    except Exception:
      # log the failure and bail out
      log.warn("Could not retrieve FOO")
      return

It's also poor form to "return True" in the exit method of the context manager. If there is no exception then that's not needed at all, and if there is an exception ... well, that code will swallow AttributeError and NameError and ZeroDivisionError, and leave people confused as to the source of the error.