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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_xyz(self, list_of_names=None):
 """Get xyz coordinates for these electrodes Parameters list_of_names : list of str list of electrode names to use Returns ------- list of tuples of 3 floats (x, y, z) list of xyz coordinates for all the electrodes TODO ---- coordinate system of electrodes """

        if list_of_names is not None:
            filter_lambda = lambda x: x['name'] in list_of_names
        else:
            filter_lambda = None

        return self.electrodes.get(filter_lambda=filter_lambda,
                                   map_lambda=lambda e: (float(e['x']),
                                                         float(e['y']),
                                                         float(e['z'])))