old_ip if not exist || empty

init.py

@@ -12,26 +12,29 @@ while True:
         # lo crea
         f = open("old_ip.txt", "a")
         # escribe la palabra ip
-        f.write("ip")
+        f.write("ip nueva")
         f.close()
 
+    # si existe y esta vacia
     with open("old_ip.txt", "r") as f:
         contenido = f.read()
-        if contenido != '':
-            old_ip = f.readlines()[0].strip()
-        else:
+        if contenido == '':
             f = open("old_ip.txt", "w")
-            f.write("ip")
+            f.write("ip vacia")
             f.close()
-    if ip != old_ip:
-        # son distintas
-        f = open("old_ip.txt", "w")
-        f.write(ip)
-        f.close()
-        # publica en telegram
-        res = requests.get(
-            "https://api.telegram.org/bot1636534751:AAH_0Mwsv8Dwk9Nd"
-            "CQhKyt_TA5uoaJhC_XE/sendMessage?chat_id=3058130&text="
-            "La nueva Ip para su Raspberry es: " + ip
-        )
+
+    # si existe y tiene algo escrito
+    with open("old_ip.txt", "r") as f:
+        old_ip = f.readlines()[0].strip()
+        if ip != old_ip:
+            # son distintas
+            f = open("old_ip.txt", "w")
+            f.write(ip)
+            f.close()
+            # publica en telegram
+            res = requests.get(
+                "https://api.telegram.org/bot1636534751:AAH_0Mwsv8Dwk9Nd"
+                "CQhKyt_TA5uoaJhC_XE/sendMessage?chat_id=3058130&text="
+                "La nueva Ip para su Raspberry es: " + ip
+            )
     sleep(5 * 60)