Deduping with networkx.py

import networkx as nx

Graphtype = nx.Graph()

with open('result.csv', "r") as data:
    # skip the header
    next(data, None)
    # parse into the graph
    G = nx.parse_edgelist(data, delimiter=',', create_using=Graphtype)
    
# append the individual subgraph nodes to a list
results = []
for x in (G.subgraph(c) for c in nx.connected_components(G)):
    results.append(x.nodes())
    
parent = ''
with open('output.csv', "w") as output:
    for group in results:
        parent = list(group)[0]    
        for match in group:
            output.write(','.join([parent, match]) + "\n")