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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 scan_timestamp(self, tbuf):
        '''scan forward looking in a tlog for a timestamp in a reasonable range'''
        while True:
            (tusec,) = struct.unpack('>Q', tbuf)
            t = tusec * 1.0e-6
            if abs(t - self._last_timestamp) <= 3*24*60*60:
                break
            c = self.f.read(1)
            if len(c) != 1:
                break
            tbuf = tbuf[1:] + c
        return t