A list of primes shouldn't be very hard to find, figure out how to enter them into your program and then just compare that list to what your function says!

Here's a bunch.. https://primes.utm.edu/lists/small/10000.txt

It consists of a bunch of lines, each containing a couple of numbers..

So one would read the lines until there aren't any more

and for each line you would split it on whitespace and convert each

"word" into an integer.

Add all those integers to a set (a set supports constant-time checking of whether a

value exists in the set, whereas a list would have to iterate through itself, comparing

each of its elements to the value you are looking for) .. and then iterate through

numbers 0 up to the highest prime that you entered, if your function reports the number

to be a prime, then it should be in the set, and if not, then it shouldn't be there.

```
primes = set()
# Read numbers until an empty line is entered:
in_data = raw_input()
while in_data != "":
# Convert in_data to integers and add them to the set
primes.update(int(n) for n in in_data.split())
in_data = raw_input()
```

And then you'd make a loop which iterates through 0 up to the highest prime you included in the user input:

```
for n in range(max(primes)+1):
correct_answer = n in primes
my_result = is_prime(n)
if my_result == correct_answer:
print 'my_result(%s) -> %s OK!' % (n, my_result)
else:
print 'my_result(%s) -> %s but correct answer is: %s' % (n, my_result, correct_answer)
break
```