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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 check_completeness(self):
 """Raise a |RuntimeError| if the |IOSequence.series| contains at least one |numpy.nan| value, if option |Options.checkseries| is enabled. Traceback (most recent call last):
 RuntimeError: The series array of sequence `seq` contains 10 nan values. Traceback (most recent call last):
 RuntimeError: The series array of sequence `seq` contains 1 nan value. """

        if hydpy.pub.options.checkseries:
            isnan = numpy.isnan(self.series)
            if numpy.any(isnan):
                nmb = numpy.sum(isnan)
                valuestring = 'value' if nmb == 1 else 'values'
                raise RuntimeError(
                    f'The series array of sequence '
                    f'{objecttools.devicephrase(self)} contains '
                    f'{nmb} nan {valuestring}.')