<｜begin▁of▁sentence｜>### Instruction:
Imagine you're coordinating a relief effort after a natural disaster, and you're utilizing a network graph that represents various aid stations and the supply paths between them. The edges of this graph are weighted, signifying the difficulty or cost of transporting supplies along these routes, with these weights as real numbers to allow for precise calculations.

For efficiency and to ensure that our logistical models are accurate, you need to confirm that all weights in the graph are legitimate real numbers. Can we employ the 'is_real_weighted' function available in the graspologic API? This function would provide a quick check to guarantee that our model correctly reflects the real-world scenario we are dealing with. It is essential that our graph's integrity is verified, so we can focus on delivering aid where it's most needed without any computational hindrances.
### Response:
import networkx as nx
from graspologic.preconditions import is_real_weighted

G = nx.Graph()
G.add_edge(1, 2, weight=3.5)
G.add_edge(2, 3, weight=2.1)
G.add_edge(1, 3, weight=-4.0)  # Negative weights are allowed as long as they are real numbers

# Check if all edges have a real number as the weight attribute
canonical = is_real_weighted(G, weight_attribute='weight')
print(canonical)
<|EOT|>
