Sets a value in this row.

        The cell is determined by the ``row_key`` of this :class:`DirectRow`
        and the ``column``. The ``column`` must be in an existing
        :class:`.ColumnFamily` (as determined by ``column_family_id``).

        .. note::

            This method adds a mutation to the accumulated mutations on this
            row, but does not make an API request. To actually
            send an API request (with the mutations) to the Google Cloud
            Bigtable API, call :meth:`commit`.

        For example:

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

        :type column_family_id: str
        :param column_family_id: The column family that contains the column.
                                 Must be of the form
                                 ``[_a-zA-Z0-9][-_.a-zA-Z0-9]*``.

        :type column: bytes
        :param column: The column within the column family where the cell
                       is located.

        :type value: bytes or :class:`int`
        :param value: The value to set in the cell. If an integer is used,
                      will be interpreted as a 64-bit big-endian signed
                      integer (8 bytes).

        :type timestamp: :class:`datetime.datetime`
        :param timestamp: (Optional) The timestamp of the operation.

def set_cell(self, column_family_id, column, value, timestamp=None):
        """Sets a value in this row.

        The cell is determined by the ``row_key`` of this :class:`DirectRow`
        and the ``column``. The ``column`` must be in an existing
        :class:`.ColumnFamily` (as determined by ``column_family_id``).

        .. note::

            This method adds a mutation to the accumulated mutations on this
            row, but does not make an API request. To actually
            send an API request (with the mutations) to the Google Cloud
            Bigtable API, call :meth:`commit`.

        For example:

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

        :type column_family_id: str
        :param column_family_id: The column family that contains the column.
                                 Must be of the form
                                 ``[_a-zA-Z0-9][-_.a-zA-Z0-9]*``.

        :type column: bytes
        :param column: The column within the column family where the cell
                       is located.

        :type value: bytes or :class:`int`
        :param value: The value to set in the cell. If an integer is used,
                      will be interpreted as a 64-bit big-endian signed
                      integer (8 bytes).

        :type timestamp: :class:`datetime.datetime`
        :param timestamp: (Optional) The timestamp of the operation.
        """
        self._set_cell(column_family_id, column, value, timestamp=timestamp, state=None)