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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 remove(self, what, call):
 """ remove an observer what: (string | array) state fields to observe call: (function) when not given, decorator usage is assumed. The call function should have 2 parameters: - previousValue, - actualValue """

        type = observerTypeEnum.typeOf(what)
        self._observers.remove({
                                    "observing": what,
                                    "type": type,
                                    "call": call
                                 })