Generate trip name from accommodation locations.

agenda/types.py

@@ -2,11 +2,11 @@
 
 import collections
 import datetime
-from datetime import date
 import functools
 import typing
 from collections import defaultdict
 from dataclasses import dataclass, field
+from datetime import date
 
 import emoji
 from pycountry.db import Country
@@ -77,6 +77,9 @@ class Trip:
             event["title"] for event in self.events
         ] or self.titles_from_travel()
 
+        if not titles:
+            titles = [acc["location"] for acc in self.accommodation]
+
         return format_list_with_ampersand(titles) or "[unnamed trip]"
 
     def titles_from_travel(self) -> list[str]: