How to convert this for a loop to a list comprehension?

Question

I have a for loop as follows:

for i in conversion: for f in glob.glob(i): print(os.path.getsize(f)) 

I want to convert this to a list comprehension:

Tried this:

 [os.path.getsize(f) for f in glob.glob(i) for i in conversion] 

but does not work.

Answer 1

The order of for loops in the understanding of a double list is the same order you would use with nested loops:

 [os.path.getsize(f) for i in conversion for f in glob.glob(i)] 

This is a bit confusing because you expect the inner loop to be more “inner”, but as soon as you realize that this is the same order as the nested loop, everything is simple :)