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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 _required_segments(self, sampfrom, sampto):
 """ Determine the segments and the samples within each segment in a multi-segment record, that lie within a sample range. Parameters sampfrom : int The starting sample number to read for each channel. sampto : int The sample number at which to stop reading for each channel. """


        # The starting segment with actual samples
        if self.layout == 'fixed':
            startseg = 0
        else:
            startseg = 1

        # Cumulative sum of segment lengths (ignoring layout segment)
        cumsumlengths = list(np.cumsum(self.seg_len[startseg:]))
        # Get first segment
        seg_numbers = [[sampfrom < cs for cs in cumsumlengths].index(True)]
        # Get final segment
        if sampto == cumsumlengths[len(cumsumlengths) - 1]:
            seg_numbers.append(len(cumsumlengths) - 1)
        else:
            seg_numbers.append([sampto <= cs for cs in cumsumlengths].index(True))

        # Add 1 for variable layout records
        seg_numbers = list(np.add(seg_numbers,startseg))

        # Obtain the sampfrom and sampto to read for each segment
        if seg_numbers[1] == seg_numbers[0]:
            # Only one segment to read
            seg_numbers = [seg_numbers[0]]
            # The segment's first sample number relative to the entire record
            segstartsamp = sum(self.seg_len[0:seg_numbers[0]])
            readsamps = [[sampfrom-segstartsamp, sampto-segstartsamp]]

        else:
            # More than one segment to read
            seg_numbers = list(range(seg_numbers[0], seg_numbers[1]+1))
            readsamps = [[0, self.seg_len[s]] for s in seg_numbers]

            # Starting sample for first segment.
            readsamps[0][0] = sampfrom - ([0] + cumsumlengths)[seg_numbers[0]-startseg]

            # End sample for last segment
            readsamps[-1][1] = sampto - ([0] + cumsumlengths)[seg_numbers[-1]-startseg]

        return (seg_numbers, readsamps)