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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 from_pb(cls, cell_pb):
 """Create a new cell from a Cell protobuf. :type cell_pb: :class:`._generated.data_pb2.Cell` :param cell_pb: The protobuf to convert. :rtype: :class:`Cell` :returns: The cell corresponding to the protobuf. """

        if cell_pb.labels:
            return cls(cell_pb.value, cell_pb.timestamp_micros, labels=cell_pb.labels)
        else:
            return cls(cell_pb.value, cell_pb.timestamp_micros)