Get a time series of cells stored on this instance.

        For example:

        .. literalinclude:: snippets_table.py
            :start-after: [START bigtable_row_cell_values]
            :end-before: [END bigtable_row_cell_values]

        Args:
            column_family_id (str): The ID of the column family. Must be of the
                form ``[_a-zA-Z0-9][-_.a-zA-Z0-9]*``.
            column (bytes): The column within the column family where the cells
                are located.
            max_count (int): The maximum number of cells to use.

        Returns:
            A generator which provides: cell.value, cell.timestamp_micros
                for each cell in the list of cells

        Raises:
            KeyError: If ``column_family_id`` is not among the cells stored
                in this row.
            KeyError: If ``column`` is not among the cells stored in this row
                for the given ``column_family_id``.

def cell_values(self, column_family_id, column, max_count=None):
        """Get a time series of cells stored on this instance.

        For example:

        .. literalinclude:: snippets_table.py
            :start-after: [START bigtable_row_cell_values]
            :end-before: [END bigtable_row_cell_values]

        Args:
            column_family_id (str): The ID of the column family. Must be of the
                form ``[_a-zA-Z0-9][-_.a-zA-Z0-9]*``.
            column (bytes): The column within the column family where the cells
                are located.
            max_count (int): The maximum number of cells to use.

        Returns:
            A generator which provides: cell.value, cell.timestamp_micros
                for each cell in the list of cells

        Raises:
            KeyError: If ``column_family_id`` is not among the cells stored
                in this row.
            KeyError: If ``column`` is not among the cells stored in this row
                for the given ``column_family_id``.
        """
        cells = self.find_cells(column_family_id, column)
        if max_count is None:
            max_count = len(cells)

        for index, cell in enumerate(cells):
            if index == max_count:
                break

            yield cell.value, cell.timestamp_micros