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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 set_observable(self,tseq,qseq):
 """Set the observable sequence data :param tseq: target sequence (from the homopolymer) :param qseq: query sequence ( from the homopolymer) :type tseq: string :type qseq: string """

    tnt = None
    qnt = None
    if len(tseq) > 0: tnt = tseq[0]
    if len(qseq) > 0: qnt = qseq[0]
    self._observable.set(len(tseq),len(qseq),tnt,qnt)