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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 _data_in_prefetch_buffers(self, offset):
 """ if a block of data is present in the prefetch buffers, at the given offset, return the offset of the relevant prefetch buffer. otherwise, return None. this guarantees nothing about the number of bytes collected in the prefetch buffer so far. """

        k = [i for i in self._prefetch_data.keys() if i <= offset]
        if len(k) == 0:
            return None
        index = max(k)
        buf_offset = offset - index
        if buf_offset >= len(self._prefetch_data[index]):
            # it's not here
            return None
        return index