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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 _tobinarray_really(self, start, end, pad, size):
 """Return binary array."""

        if pad is None:
            pad = self.padding
        bin = array('B')
        if self._buf == {} and None in (start, end):
            return bin
        if size is not None and size <= 0:
            raise ValueError("tobinarray: wrong value for size")
        start, end = self._get_start_end(start, end, size)
        for i in range_g(start, end+1):
            bin.append(self._buf.get(i, pad))
        return bin