How to Test Value of Radio Group

@Teodor…

I have a radio group as shown below, and I want to test the value it is set to… so to say:

dmx-show="(RADIO_GROUP.value=='copy') || (RADIO_GROUP.value=='modify')"

How do I name the radio group to be able to make this test?

Thanks!
Antony.

<div class="form-check">
	<input class="form-check-input" type="radio" value="" id="new" name="wizard_action">
	<label class="form-check-label" for="new">Define new activity</label><br>
	<input class="form-check-input" type="radio" value="" id="copy" name="wizard_action">
	<label class="form-check-label" for="copy">Copy existing activity</label><br>
	<input class="form-check-input" type="radio" value="" id="modify" name="wizard_action">
	<label class="form-check-label" for="modify">Modify existing activity</label><br>
</div>