Agreed.

nice one

simplicity can cause trouble IMO

besides what's the harm of just making it clear

i dont agree with the top solution.
If you got an r = 0 as your param in the random test like I do, that solution fail.

I suggest adding that into the sample test.
like arithmetic_sequence_elements(1, 0, 5)
I am pretty sure the top one failed on this

i dont agree with this solution.
If you got an r = 0 in your param like I do, this solution fail

Yes I agree on this.
Better bearing performance in mind

you can do this in one line by datetime.datetime.strptime("","%d-%m-%Y")

this is a decorator,make it a static method,just for stylish.
if you dont have this decor,you will have to

1. initialize an instance of class filenameextractor, then call the method bounded to that object
2. the method must have a para called 'self'

similar idea but better than mine. Nice work

Didn't really get what the problem want....

I have seen many of the solutions(mine included) did not solve for the cases below:

1. parameters could have more than 1 letter i.e. ?aaa= 2
2. what if your only parameter is in the to_strip list?

Could add these two to make it more interesting ; )

fail if you have a parameter with more than one character

but still good anyway