Test for `pester` version using `pester`

I have a set of pester tests for a PowerShell module which use the v4.0+ should operator -FileContentMatch. When these tests are run on a machine with an earlier v3.x version of pester, there is a wave of error messages, none of which exactly point out the problem.

I'd like to write a simple pester test to check for a minimum version and print an explanation / fix for the user / tester.

The extra complication is that pester can be run directly as a script without being installed as a module on the machine.

I've looked at using $(Get-Module -ListAvailable -name "Pester").version to pull out the pester version, but it only sees the PowerShell-"installed" module, not the currently executing version, which, as noted, could be different.

Some signal passed from pester would be fine, but I don't see that pester provides any meta-information to the test scripts (ie, a version environment variable).

Any thoughts on a solution?