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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 pages(self):
 """A generator of all pages in the stream. Returns: types.GeneratorType[google.cloud.bigquery_storage_v1beta1.ReadRowsPage]: A generator of pages. """

        # Each page is an iterator of rows. But also has num_items, remaining,
        # and to_dataframe.
        avro_schema, column_names = _avro_schema(self._read_session)
        for block in self._reader:
            self._status = block.status
            yield ReadRowsPage(avro_schema, column_names, block)