I need a Groovy Scriptrunner Script

Job ID: 33126097

Budget: $10 – $30 USD

I am trying to update a custom "Severity" field in Jira that is dependent on a numerical value of another customer field "Score".

If 9 - 10, Severity == Critical
If 7 - 8.9, Severity == High
If 4 - 6.9, Severity == Medium
If .1 - 3.9, Severity == Low

needs proper error messaging if user inputs number <.1 or >10
Severity field needs to be able to be updated when Score is edited on create or when updated
Related categories: JavaScript Atlassian Jira