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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_global_attributes(self, ds):
 """ Check all global NC attributes for existence. :param netCDF4.Dataset ds: An open netCDF dataset """

        return [
            self._has_attr(ds, 'acknowledgement', 'Platform Sponsor'),
            self._has_attr(ds, 'publisher_email', 'Station Publisher Email'),
            self._has_attr(ds, 'publisher_email', 'Service Contact Email', BaseCheck.MEDIUM),
            self._has_attr(ds, 'institution', 'Service Provider Name', BaseCheck.MEDIUM),
            self._has_attr(ds, 'publisher_name', 'Service Contact Name', BaseCheck.MEDIUM),
            self._has_attr(ds, 'Conventions', 'Data Format Template Version', BaseCheck.MEDIUM),
            self._has_attr(ds, 'publisher_name', 'Station Publisher Name', BaseCheck.HIGH),
        ]