If you put the following Code into a Python interpreter
import random
print(random.randrange(1,10))
then you will print a random integer (a full number) from 1 to 9.
The 1 is included and the 10 isn't.
I also think that's a bit "unconventional" for a raffle with 50 people
You could go ahead and use the following code:
import random
print(random.randrange(1,51)
This will include 1-50.
As others have mentioned before. You could also pick a bitcoin block in the future and let the last 2 digits of the hash of the block decide the winner. If its above 50, just go with the next block.
Just make sure to announce the block you chose before it is mined