<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def lookup(self, iterable, gather=False):
 """Call the lookup on the root node with the given parameters. Args iterable(index or key):
 Used to retrive nodes from tree gather(bool):
 this is passed down to the root node lookup Notes: max_edit_distance and match_threshold come from the init """

        for result in self.root.lookup(iterable,
                                       gather=gather,
                                       edit_distance=0,
                                       max_edit_distance=self.max_edit_distance,
                                       match_threshold=self.match_threshold):
            yield result