twig: Handle dash in JSON

If JSON contains some dashes (“-“) in the keys, the usual way of twig does not work. Here you finde how to solve this: JSON:

twig-code for plugin template manager:
id: {{id}}<br>
mvalue: {{attributes.mvalue}}<br>
test-value: {{attributes.test-value}}<br>
test-value: {{ attribute(attributes, 'test-value') }}<br>

[jsoncontentimporterpro url= parser=twig id=ID_TEMPLATE_MANAGER]

Example: id: 327456
mvalue: 543543.067567575
test-value: 0
test-value: 2352.07597459064