need an authentication file (in config.cfg format) to access to database

[dier-zhang]

When I tried to reproduce the code here,I ran into a problem that looked like an authentication file (in config.cfg format) was missing to access the database. The error message is as follows:
pymongo.errors.ServerSelectionTimeoutError: rmg.mit.edu:27018: [Errno -2] Name or service not known, Timeout: 30s, Topology Description: <TopologyDescription id: 6388a7abbf21b29a7bc4e82e, topology_type: Single, servers: [<ServerDescription ('rmg.mit.edu', 27018) server_type: Unknown, rtt: None, error=AutoReconnect('rmg.mit.edu:27018: [Errno -2] Name or service not known')>]>