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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_region(self):
 """Validate region was passed in and is a valid GCE zone."""

        if not self.region:
            raise GCECloudException(
                'Zone is required for GCE cloud framework: '
                'Example: us-west1-a'
            )

        try:
            zone = self.compute_driver.ex_get_zone(self.region)
        except Exception:
            zone = None

        if not zone:
            raise GCECloudException(
                '{region} is not a valid GCE zone. '
                'Example: us-west1-a'.format(
                    region=self.region
                )
            )