Handle missing space launch

update.py

@@ -99,10 +99,15 @@ Agenda: https://edwardbetts.com/agenda/
 
 
 def report_space_launch_change(
-    config: flask.config.Config, prev_launch: StrDict, cur_launch: StrDict
+    config: flask.config.Config, prev_launch: StrDict | None, cur_launch: StrDict | None
 ) -> None:
     """Send mail to announce change to space launch data."""
-    subject = f'Change to {cur_launch["name"]}'
+    if cur_launch:
+        name = cur_launch["name"]
+    else:
+        assert prev_launch
+        name = prev_launch["name"]
+    subject = f"Change to {name}"
 
     body = f"""
 A space launch of interest was updated.
@@ -119,9 +124,11 @@ New launch data
     send_mail(config, subject, body)
 
 
-def get_launch_by_slug(data: StrDict, slug: str) -> StrDict:
+def get_launch_by_slug(data: StrDict, slug: str) -> StrDict | None:
     """Find last update for space launch."""
-    return {item["slug"]: typing.cast(StrDict, item) for item in data["results"]}[slug]
+    return {item["slug"]: typing.cast(StrDict, item) for item in data["results"]}.get(
+        slug
+    )
 
 
 def update_thespacedevs(config: flask.config.Config) -> None:
@@ -142,7 +149,10 @@ def update_thespacedevs(config: flask.config.Config) -> None:
 
     for slug in config["FOLLOW_LAUNCHES"]:
         prev, cur = prev_launches[slug], cur_launches[slug]
-        if prev["last_updated"] != cur["last_updated"]:
+        if prev is None and cur is None:
+            continue
+        if prev and cur and prev["last_updated"] == cur["last_updated"]:
+            continue
         report_space_launch_change(config, prev, cur)
 
     time_taken = time() - t0