Map Rest Connector Object Response into a Process Variable (complex Business Object with MULTIPLE Business OBject, including LISTs)

I am calling this service I've found in other examples https://www.metaweather.com/api/location/44418/, from a REST Connector out and it returns a complex structure.

All the examples I've found extract a single STRING from the complex structure (from bodyAsObject) without issues. I could do so also without any problem.

Parsing contract variables coming from a form

Hi everybody,
I'm working in a process with a mailing connector. I have a form with a table widget to select some lines. When I select these lines I send them to a contract variable (multiple text). What I'm trying is parsing the content of this variable to fit data in the body of my email. At this moment I have only a beautiful string like this:
" [{persistenceId=111, .., field1=john, field2=snow,..}, {persistenceId=200, ..., field1=mary, field2=skye,..}] ".

I'm new in this kind of code. Perhaps someone could give me a way to try this.