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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 _setbitpos(self, pos):
 """Move to absolute postion bit in bitstream."""

        if pos < 0:
            raise ValueError("Bit position cannot be negative.")
        if pos > self.len:
            raise ValueError("Cannot seek past the end of the data.")
        self._pos = pos