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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 read_bit(self):
 """ Read a single boolean value, returns 0 or 1. Convience for single bit fields. Will raise BufferUnderflow if there's not enough bytes in the buffer. """

        # Perform a faster check on underflow
        if self._pos >= self._end_pos:
            raise self.BufferUnderflow()
        result = ord(self._input[self._pos]) & 1
        self._pos += 1
        return result