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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 append(self, item):
 """ append a single item to the array, growing the wrapped numpy array if necessary """

        try:
            self._data[self._position] = item
        except IndexError:
            self._grow()
            self._data[self._position] = item
        self._position += 1
        return self