Improve article_title_to_search_query function

Add more detailed docstring

web_view.py

@@ -35,17 +35,41 @@ class Hit(typing.TypedDict):
     timestamp: str
 
 
-re_disambig = re.compile(r"^(.*) \((.*)\)$")
-
-
 def load_examples() -> list[dict[str, str | int]]:
     """Load examples."""
     return [json.loads(line) for line in open("examples")]
 
 
 def article_title_to_search_query(title: str) -> str:
-    """Convert from article title to search query string."""
+    """
-    m = re_disambig.match(title)
+    Convert a Wikipedia article title to a search query string.
+
+    This function takes a Wikipedia article title and parses it to create a
+    search query. If the title contains disambiguation text in parentheses,
+    it separates the main title and the disambiguation text and formats them
+    into a search query using an AND operator. If there's no disambiguation text,
+    the title is used as is for the search query.
+
+    The search query is formatted such that the main title and the disambiguation
+    text (if present) are enclosed in double quotes and connected with 'AND'.
+    This format is useful for precise search engine queries.
+
+    Args:
+        title (str): The Wikipedia article title, possibly including disambiguation
+                     text in parentheses.
+
+    Returns:
+        str: A formatted search query string. If disambiguation text is present,
+             returns '"[main title]" AND "[disambiguation text]"'. Otherwise,
+             returns '"[title]"'.
+
+    Example:
+        >>> article_title_to_search_query("Python (programming language)")
+        '"Python" AND "programming language"'
+        >>> article_title_to_search_query("London")
+        '"London"'
+    """
+    m = re.match(r"^(.*) \((.*)\)$", title)
     return f'"{m.group(1)}" AND "{m.group(2)}"' if m else f'"{title}"'