A generic object to hold data in python

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From: http://stackoverflow.com/questions/1878710/struct-objects-in-python

A most concise way to make “a generic object to which you can assign/fetch attributes” is probably:

item = lambda: 0
item.len = 4
item.data = list(map(int, input().rstrip().split(" ")))

At first, this boggled my mind. But it’s actually simple. The lambda creates a function object; this one happens to be a trivial function that returns 0. Function objects have certain attributes, among them a func_dict member. This works because it works for any function object; you can bind values to names associated with any function object. I have used that to provide “enumerated” flags that can be used when calling the function: foo(0, foo.ALTERNATE_MODE) This made-up example shows calling a function with an optional flag that requests some sort of alternate mode. – steveha Dec 31 ’09 at 22:09

More about python lambda function: (from: http://www.secnetix.de/olli/Python/lambda_functions.hawk)

Python supports the creation of anonymous functions at runtime, using a construct called “lambda”. This is not exactly the same as lambda in functional programming languages, but it is a very powerful concept that’s well integrated into Python and is often used in conjunction with typical functional concepts like filter() , map()  and reduce() .

>>> def f (x): return x**2
...
>>> print f(8)
64
>>>
>>> g = lambda x: x**2
>>>
>>> print g(8)
64