Here is the script:

import pandas as pd
import networkx as nx

data = {
    "Product": ["A", "B", "C", "D", "E"],
    "Selling_Locations": [[1, 2, 3], [2, 5], [7, 8, 9, 10], [5, 4], [10, 11]]
}

df = pd.DataFrame(data)

G = nx.Graph()

for product in df["Product"]:
    G.add_node(product)

for i in range(len(df)):
    for j in range(i + 1, len(df)):
        if set(df["Selling_Locations"][i]) & set(df["Selling_Locations"][j]):
            G.add_edge(df["Product"][i], df["Product"][j])

groups = list(nx.connected_components(G))

for i, group in enumerate(groups, 1):
    print(f"Group {i}: {sorted(group)}")

Ouput: