Expression trees in python
This is an attempt to implement something similar to LINQ expressions trees(at least in purpose) in python, in a clean, simple and pythonic way(where 'pythonic' means clean and simple, and taking advantage of the features of the language).
A use case is to allow to define a generic, abstract representation of different kinds of expressions(e.g. boolean expressions), that can then be independently compiled/converted into another representation(e.g. JSON, SQL), or evaluated directly in python, under a context.