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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 _aux_type(self, i):
 """Data-type of the array's ith aux data. Returns ------- numpy.dtype This BaseSparseNDArray's aux data type. """

        aux_type = ctypes.c_int()
        check_call(_LIB.MXNDArrayGetAuxType(self.handle, i, ctypes.byref(aux_type)))
        return _DTYPE_MX_TO_NP[aux_type.value]