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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 _get_branches(self, closed=False):
 """ Get's branches for this repository Returns only not closed branches by default :param closed: return also closed branches for mercurial """


        if self._empty:
            return {}

        def _branchtags(localrepo):
            """
            Patched version of mercurial branchtags to not return the closed
            branches

            :param localrepo: locarepository instance
            """

            bt = {}
            bt_closed = {}
            for bn, heads in localrepo.branchmap().iteritems():
                tip = heads[-1]
                if 'close' in localrepo.changelog.read(tip)[5]:
                    bt_closed[bn] = tip
                else:
                    bt[bn] = tip

            if closed:
                bt.update(bt_closed)
            return bt

        sortkey = lambda ctx: ctx[0]  # sort by name
        _branches = [(safe_unicode(n), hex(h),) for n, h in
                     _branchtags(self._repo).items()]

        return OrderedDict(sorted(_branches, key=sortkey, reverse=False))