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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 build_trees(self):
        "Build an unrooted consensus tree from filtered clade counts."

        # storage
        nodes = {}
        idxarr = np.arange(len(self.fclade_counts[0][0]))
        queue = []

        ## create dict of clade counts and set keys
        countdict = defaultdict(int)
        for clade, count in self.fclade_counts:
            mask = np.int_(list(clade)).astype(np.bool)
            ccx = idxarr[mask]
            queue.append((len(ccx), frozenset(ccx)))
            countdict[frozenset(ccx)] = count

        while queue:
            queue.sort()
            (clade_size, clade) = queue.pop(0)
            new_queue = []

            # search for ancestors of clade
            for (_, ancestor) in queue:
                if clade.issubset(ancestor):
                    # update ancestor such that, in the following example:
                    # ancestor == {1, 2, 3, 4}
                    # clade == {2, 3}
                    # new_ancestor == {1, {2, 3}, 4}
                    new_ancestor = (ancestor - clade) | frozenset([clade])
                    countdict[new_ancestor] = countdict.pop(ancestor)
                    ancestor = new_ancestor

                new_queue.append((len(ancestor), ancestor))

            # if the clade is a tip, then we have a name
            if clade_size == 1:
                name = list(clade)[0]
                name = self.namedict[name]
            else:
                name = None

            # the clade will not be in nodes if it is a tip
            children = [nodes.pop(c) for c in clade if c in nodes]
            node = TreeNode(name=name)
            for child in children:
                node.add_child(child)
            if not node.is_leaf():
                node.dist = int(round(100 * countdict[clade]))
                node.support = int(round(100 * countdict[clade]))
            else:
                node.dist = int(100)
                node.support = int(100)

            nodes[clade] = node
            queue = new_queue
        nodelist = list(nodes.values())
        tre = nodelist[0]

        #tre.unroot()
        ## return the tree and other trees if present
        self.ttree = ToyTree(tre.write(format=0))
        self.ttree._coords.update()
        self.nodelist = nodelist