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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 drop(self):
 """Drop this database. See https://cloud.google.com/spanner/reference/rpc/google.spanner.admin.database.v1#google.spanner.admin.database.v1.DatabaseAdmin.DropDatabase """

        api = self._instance._client.database_admin_api
        metadata = _metadata_with_prefix(self.name)
        api.drop_database(self.name, metadata=metadata)