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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 itemsize(self):
 """ Return the size of the dtype of the item of the underlying data. .. deprecated:: 0.23.0 """

        warnings.warn("{obj}.itemsize is deprecated and will be removed "
                      "in a future version".format(obj=type(self).__name__),
                      FutureWarning, stacklevel=2)
        return self._ndarray_values.itemsize