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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 update_hslice(self, blob):
 """Update the Hamiltonian slice proposal scale based on the relative amount of time spent moving vs reflecting."""


        nmove, nreflect = blob['nmove'], blob['nreflect']
        ncontract = blob.get('ncontract', 0)
        fmove = (1. * nmove) / (nmove + nreflect + ncontract + 2)
        norm = max(self.fmove, 1. - self.fmove)
        self.scale *= math.exp((fmove - self.fmove) / norm)