<｜begin▁of▁sentence｜>### Instruction:
Given a graph with nodes positioned in 2D space, calculate the bounding box of the layout and contract this bounding box by specific margins (dx and dy). How can you achieve this using NetworkX?
### Response:
import networkx as nx

# Create a graph
g = nx.Graph()
g.add_edges_from([(1,2), (2,3), (3,4), (4,5)])

# Calculate the bounding box of a position layout
pos = nx.spring_layout(g)
bb = nx.utils.BoundingBox(pos.values())

# Contract the bounding box by some margins (dx and dy)
dx, dy = 0.1, 0.1
contracted_bb = bb.contract(dx, dy)

print(f'Original BoundingBox: {bb}')
print(f'Contracted BoundingBox: {contracted_bb}')
<|EOT|>
