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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def from_dict(d):
 """Transform the dict to a person object and return the person."""

        query_params_match = d.get('@query_params_match')
        sources = [Source.from_dict(source) for source in d.get('sources', [])]
        fields = Person.fields_from_dict(d)
        return Person(fields=fields, sources=sources,
                      query_params_match=query_params_match)