<｜begin▁of▁sentence｜>### Instruction:
As a data analyst at a popular science journal, your team wants to explore the collaboration patterns within the field of condensed matter physics using the Condensed Matter collaborations graph of 2005. The graph is stored in a gml file named "cond-mat-2005.gml". Your team is interested in using the Louvain method, available in the cdlib library, for community detection to identify key collaborative communities. Additionally, they would like to read and write the community structure to and from a JSON file for further analysis and visualization. How would you approach this task, and what are the steps involved in using the Louvain method and working with JSON files in this context?
### Response:
import networkx as nx
from cdlib import algorithms, readwrite

g = nx.read_gml('cond-mat-2005.gml')
coms = algorithms.louvain(g)
readwrite.write_community_json(coms, 'communities.json')
coms_from_json = readwrite.read_community_json('communities.json')
<|EOT|>
