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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 range(self):
 """Return the range the transcript loci covers :return: range :rtype: GenomicRange """

    chrs = set([x.range.chr for x in self.get_transcripts()])
    if len(chrs) != 1: return None
    start = min([x.range.start for x in self.get_transcripts()])
    end = max([x.range.end for x in self.get_transcripts()])
    return GenomicRange(list(chrs)[0],start,end)