About a list comprehension to transform an input list

[Julio Sergio]

>From a sequence of numbers, I'm trying to get a list that does something to even 
numbers but leaves untouched the odd ones, say:

[0,1,2,3,4,...] ==> [100,1,102,3,104,...]

I know that this can be done with an auxiliary function, as follows:

->>> def filter(n):
...     if (n%2 == 0):
...         return 100+n
...     return n
... 
->>> L = range(10)
->>> [filter(n) for n in L]
[100, 1, 102, 3, 104, 5, 106, 7, 108, 9]

I wonder whether there can be a single list comprehension expression to get this 
result without the aid of the auxiliary function.

Do you have any comments on this?

Thanks,
--Sergio.