<｜begin▁of▁sentence｜>### Instruction:
As an information architect working with a team designing a digital information system for a transportation network, we've received a "graph_data.gml" file containing details of the road network. We need to use the "layout_umap" function in the igraph API to compute the 2D UMAP layout for visualizing the road network data.
### Response:
from igraph import Graph

# Read the graph data from a file
g = Graph.Read_GML('graph_data.gml')

# Use UMAP layout
dim = 2 # Set the number of dimensions for the layout
layout = g.layout_umap(dim=dim)

# Use the layout for plotting or any other purpose
print(layout)
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