<｜begin▁of▁sentence｜>### Instruction:
This code snippet demonstrates the usage of the 'open_file' decorator in the NetworkX library. This utility is used to ensure proper opening and closing of files when dealing with I/O operations. The example creates a complete graph with 5 nodes and uses a decorated function to save the graph to a file in adjacency list format. What is the issue this decorator solves and how would you apply it to a function that needs to handle file operations like reading or writing a graph structure to disk?
### Response:
import networkx as nx

@nx.utils.open_file(1, 'w')
def save_graph(graph, path):
    nx.write_adjlist(graph, path)

# Create a sample graph
G = nx.complete_graph(5)
# Use the decorated function to save the graph to a file
save_graph(G, 'sample.adjlist')
<|EOT|>
