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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 mine_patterns(self, threshold):
 """ Mine the constructed FP tree for frequent patterns. """

        if self.tree_has_single_path(self.root):
            return self.generate_pattern_list()
        else:
            return self.zip_patterns(self.mine_sub_trees(threshold))