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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 name(self):
 """Gets name string from the symbol, this function only works for non-grouped symbol. Returns ------- value : str The name of this symbol, returns ``None`` for grouped symbol. """

        ret = ctypes.c_char_p()
        success = ctypes.c_int()
        check_call(_LIB.MXSymbolGetName(
            self.handle, ctypes.byref(ret), ctypes.byref(success)))
        if success.value != 0:
            return py_str(ret.value)
        else:
            return None