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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 _validate_customer_service(self):
 """ Validate input parameters if customer service is on then create directory for tarball files with correct premissions for user and group. """

        direc = self.customer_service_dir
        if not direc.exists:
            mode = 0o750
            print("Creating customer_service_dir %s with mode %s" % (direc, mode))
            direc.makedirs()
            os.chmod(direc.path, mode)

        if self.mailto is None:
            raise RuntimeError("customer_service_dir requires mailto option in scheduler.yml")