Need help writing specific text to a fine depending on if a random number is even or odd

[Yaxel]

Just like the title says
I’m trying to create a geomancy function that produces a random number between 1 and 10. If it’s odd I want it to write • and if it’s even I want it to write ••.
And when I run it multiple times it adds either output to the same file.

For example:
I roll 3.
So The text file now says
•
Then I roll again and get 8.
So now the text file says
•
••
And so on and so forth.

 

[Dimlos]

Sample macro to save random.txt in the Documents directory.
I used a shell script because of the troublesome access rights, but this can be done with the Wite to File action.