Fixed function name collision

python/server.py

@@ -33,14 +33,14 @@ def prepare_grid(grid):
   out += 'q'
   return out
 
-def serial():
+def serial_func():
   with serial.Serial('/dev/ttyACM0', 9600, timeout=1) as ser:
     with lock:
       if data != '':
         serial.write(bytes(data, 'ascii'))
         data = ''
 
-serial_thread = threading.Thread(target=serial)
+serial_thread = threading.Thread(target=serial_func)
 serial_thread.start()
 
 if __name__ == '__main__':