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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 isValid(self):
 """ Returns if the current instrument is not out for verification, calibration, out-of-date regards to its certificates and if the latest QC succeed """

        return self.isOutOfDate() is False \
            and self.isQCValid() is True \
            and self.getDisposeUntilNextCalibrationTest() is False \
            and self.isValidationInProgress() is False \
            and self.isCalibrationInProgress() is False