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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_unobserved_before(self,tlen,qlen,nt,p):
 """Set the unobservable sequence data before this base :param tlen: target homopolymer length :param qlen: query homopolymer length :param nt: nucleotide :param p: p is the probability of attributing this base to the unobserved error :type tlen: int :type qlen: int :type nt: char :type p: float """

    self._unobservable.set_before(tlen,qlen,nt,p)