Update gps_client.py make fail -1 0 0 0

gps_client.py

@@ -11,13 +11,13 @@ run this way: python3 example1.py.txt
 import gps               # the gpsd interface module
 import time
 
+try:
+
     mode = -1    
     lat = 0    
     lon = 0    
     alt = 0
 
-try:
-    
     session = gps.gps(mode=gps.WATCH_ENABLE)
     
     start = time.perf_counter()
@@ -64,6 +64,6 @@ try:
     exit(0)
     
 except:    
-    print("%d %.6f %.6f %.1f" % (mode, lat, lon, alt))
+    print("-1 0 0 0)
     exit(0)