<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def update_edge_todo(self, elev_fn, dem_proc):
 """ Can figure out how to update the todo based on the elev filename """

        for key in self.edges[elev_fn].keys():
            self.edges[elev_fn][key].set_data('todo', data=dem_proc.edge_todo)