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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 next(self) -> "ArrayEntry": """Return an instance node corresponding to the next entry. Raises: NonexistentInstance: If the receiver is the last entry of the parent array. """

        try:
            newval, naft = self.after.pop()
        except IndexError:
            raise NonexistentInstance(self.json_pointer(), "next of last") from None
        return ArrayEntry(
            self.index + 1, self.before.cons(self.value), naft, newval,
            self.parinst, self.schema_node, self.timestamp)