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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 get_vm_list(self):
 """Get the list of guests that are created by SDK return userid list"""

        action = "list all guests in database"
        with zvmutils.log_and_reraise_sdkbase_error(action):
            guests_in_db = self._GuestDbOperator.get_guest_list()
            guests_migrated = self._GuestDbOperator.get_migrated_guest_list()

        # db query return value in tuple (uuid, userid, metadata, comments)
        userids_in_db = [g[1].upper() for g in guests_in_db]
        userids_migrated = [g[1].upper() for g in guests_migrated]
        userid_list = list(set(userids_in_db) - set(userids_migrated))

        return userid_list