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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 missingDataValue(self):
 """ Returns the value to indicate missing data. """

        value =  getMissingDataValue(self._array)
        fieldNames = self._array.dtype.names

        # If the missing value attibute is a list with the same length as the number of fields,
        # return the missing value for field that equals the self.nodeName.
        if hasattr(value, '__len__') and len(value) == len(fieldNames):
            idx = fieldNames.index(self.nodeName)
            return value[idx]
        else:
            return value