style: Format watch.py with black and add newlines between functions

aider/watch.py

@@ -1,7 +1,9 @@
 from pathlib import Path
 from typing import Set
+
 from watchfiles import watch
 
+
 def is_source_file(path: Path) -> bool:
     """
     Check if a file is a source file that uses # or // style comments.
@@ -9,20 +11,42 @@ def is_source_file(path: Path) -> bool:
     """
     COMMENT_STYLE_EXTENSIONS = {
         # # style comments
-        '.py', '.r', '.rb', '.pl', '.pm', '.sh', '.bash', '.yaml', '.yml',
+        ".py",
+        ".r",
+        ".rb",
+        ".pl",
+        ".pm",
+        ".sh",
+        ".bash",
+        ".yaml",
+        ".yml",
         # // style comments
-        '.js', '.ts', '.jsx', '.tsx', '.cpp', '.c', '.h', '.hpp', '.java',
-        '.swift', '.kt', '.cs', '.go', '.rs', '.php'
+        ".js",
+        ".ts",
+        ".jsx",
+        ".tsx",
+        ".cpp",
+        ".c",
+        ".h",
+        ".hpp",
+        ".java",
+        ".swift",
+        ".kt",
+        ".cs",
+        ".go",
+        ".rs",
+        ".php",
     }
     return path.suffix.lower() in COMMENT_STYLE_EXTENSIONS
 
+
 def watch_source_files(directory: str) -> Set[str]:
     """
     Watch for changes to source files in the given directory and its subdirectories.
     Returns a set of changed file paths whenever changes are detected.
     """
     root = Path(directory)
-    
+
     # Create a filter function that only accepts source files
     def filter_func(change_type, path):
         return is_source_file(Path(path))
@@ -33,17 +57,18 @@ def watch_source_files(directory: str) -> Set[str]:
         changed_files = {str(Path(change[1])) for change in changes}
         yield changed_files
 
+
 def main():
     """Example usage of the file watcher"""
     import sys
-    
+
     if len(sys.argv) != 2:
         print("Usage: python watch.py <directory>")
         sys.exit(1)
-        
+
     directory = sys.argv[1]
     print(f"Watching source files in {directory}...")
-    
+
     try:
         for changed_files in watch_source_files(directory):
             print("\nChanged files:")
@@ -52,5 +77,6 @@ def main():
     except KeyboardInterrupt:
         print("\nStopped watching files")
 
+
 if __name__ == "__main__":
     main()