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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_monophyletic(self, values, target_attr):
 """ Returns a list of nodes matching the provided monophyly criteria. For a node to be considered a match, all `target_attr` values within and node, and exclusively them, should be grouped. :param values: a set of values for which monophyly is expected. :param target_attr: node attribute being used to check monophyly (i.e. species for species trees, names for gene family trees). """

        if type(values) != set:
            values = set(values)

        n2values = self.get_cached_content(store_attr=target_attr)

        is_monophyletic = lambda node: n2values[node] == values
        for match in self.iter_leaves(is_leaf_fn=is_monophyletic):
            if is_monophyletic(match):
                yield match