<｜begin▁of▁sentence｜>### Instruction:
Given a directed acyclic graph (DAG) with the edges [('A', 'B'), ('A', 'C'), ('B', 'D'), ('C', 'D')], determine if node 'A' is d-separated from node 'D' given the conditioning on node 'B'.
### Response:
import networkx as nx

# Create a directed acyclic graph (DAG)
G = nx.DiGraph()
G.add_edges_from([('A', 'B'), ('A', 'C'), ('B', 'D'), ('C', 'D')])

# Nodes to evaluate d-separation
x = {'A'}
y = {'D'}
z = {'B'}

# Check d-separation
separated = nx.d_separated(G, x, y, z)
print('Are nodes A and D d-separated by B?', separated)
<|EOT|>
