<｜begin▁of▁sentence｜>### Instruction:
As an Information Architect, you're tasked with designing the structure and organization of digital information and content. Imagine you're working on a project involving a complex network of transportation routes, represented as a weighted directed graph. Let's say this graph is stored in a file called "transportation_network.gml". Your goal is to analyze the efficiency of this network by calculating the average path length, considering the directionality of routes and their respective weights.

To accomplish this, you need to employ the `average_path_length` function provided by the igraph API. This function will take into account the directed nature of the transportation routes as well as their associated weights, providing valuable insights into the average distance between any two points within the network.
### Response:
from igraph import Graph

# Read the graph
graph = Graph.Read('graph_data.gml')

# Calculate the average path length
avg_path_len = graph.average_path_length(directed=True, unconn=True, weights='weight')

# Print the average path length
print('Average path length:', avg_path_len)
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