Functional Programming and python

[rusi]

Combining your two questions -- Recently:
What minimum should a person know before saying "I know Python"

And earlier this
On Sunday, August 4, 2013 10:00:35 PM UTC+5:30, Aseem Bansal wrote:
> If there is an issue in place for improving the lambda forms then that's 
> good. I wanted a link about functional programming because it is mentioned as 
> if it were a household word.

Python is not a functional programming language; however it supports most of FP better than traditional languages like C/Java.
eg with iterators/generators + itertools + functools you can do most of what lazy lists give in haskell

Some discussion here: http://stackoverflow.com/questions/1017621/why-isnt-python-very-good-for-functional-programming

[Not everything said there is correct; eg python supports currying better than haskell which is surprising considering that Haskell's surname is Curry!]

So if I may break your question into two: 
1. Why should a programmer of a non-FP language know FP?
2. What in FP should a (any|all) programmer know?

I touched upon these in two blog-posts:
1. http://blog.languager.org/2013/06/functional-programming-invades.html
2. http://blog.languager.org/2012/10/functional-programming-lost-booty.html

Also most programmers without an FP background have a poor appreciation of the centrality of recursion in CS; see
http://blog.languager.org/2012/05/recursion-pervasive-in-cs.html