A query about list

[Santanu Chatterjee]

Hello everybody,

I am very new to python. I have a query about 
list in python.

Suppose I have a list 
a = [1,[2,3,4],5,6,7,[8,9,10],11,12]
I want to know if there is any simple python
facility available that would expand the above list
to give
a = [1,2,3,4,5,6,7,8,9,10,11,12]

I know I can do that with a type() and a for/while loop,
but is there any simpler way?

Regards,
Santanu