<｜begin▁of▁sentence｜>### Instruction:
Imagine we're prepping a group of five doggies for a show, with each pup being passed along a line of five grooming stations. We want to make sure that each pooch is primped and pampered in order. The stations are set up so that each pup goes from the start to station 4 in a single file line. Now picture we're focusing on station 2, and we need to figure out which pups have already trotted through it. Could you tell us which of the doggies have made their way from the starting point up to station 2? Just think about the parade of pups needing to look their best before they reach that particular grooming spot!
### Response:
import networkx as nx
DG = nx.path_graph(5, create_using=nx.DiGraph)
print(sorted(nx.ancestors(DG, 2)))
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