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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 _subArrayShape(self):
 """ Returns the shape of the sub-array An empty tuple is returned for regular fields, which have no sub array. """

        if self._h5Dataset.dtype.fields is None:
            return tuple() # regular field
        else:
            fieldName = self.nodeName
            fieldDtype = self._h5Dataset.dtype.fields[fieldName][0]
            return fieldDtype.shape