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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 sample_row_keys(self):
 """Read a sample of row keys in the table. For example: .. literalinclude:: snippets_table.py :start-after: [START bigtable_sample_row_keys] :end-before: [END bigtable_sample_row_keys] The returned row keys will delimit contiguous sections of the table of approximately equal size, which can be used to break up the data for distributed tasks like mapreduces. The elements in the iterator are a SampleRowKeys response and they have the properties ``offset_bytes`` and ``row_key``. They occur in sorted order. The table might have contents before the first row key in the list and after the last one, but a key containing the empty string indicates "end of table" and will be the last response given, if present. .. note:: Row keys in this list may not have ever been written to or read from, and users should therefore not make any assumptions about the row key structure that are specific to their use case. The ``offset_bytes`` field on a response indicates the approximate total storage space used by all rows in the table which precede ``row_key``. Buffering the contents of all rows between two subsequent samples would require space roughly equal to the difference in their ``offset_bytes`` fields. :rtype: :class:`~google.cloud.exceptions.GrpcRendezvous` :returns: A cancel-able iterator. Can be consumed by calling ``next()`` or by casting to a :class:`list` and can be cancelled by calling ``cancel()``. """

        data_client = self._instance._client.table_data_client
        response_iterator = data_client.sample_row_keys(
            self.name, app_profile_id=self._app_profile_id
        )

        return response_iterator