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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 setStartSegment(self, segment):
 """ Set the first segment on the contour. segment can be a segment object or an index. """

        segments = self.segments
        if not isinstance(segment, int):
            segmentIndex = segments.index(segment)
        else:
            segmentIndex = segment
        if len(self.segments) < 2:
            return
        if segmentIndex == 0:
            return
        if segmentIndex >= len(segments):
            raise ValueError(("The contour does not contain a segment "
                              "at index %d" % segmentIndex))
        self._setStartSegment(segmentIndex)