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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 calc_bin(self, _bin=None):
 """ Calculate the smallest UCSC genomic bin that will contain this feature. """

        if _bin is None:
            try:
                _bin = bins.bins(self.start, self.end, one=True)
            except TypeError:
                _bin = None
        return _bin