define __str__ for objects of WaybackMachineAvailabilityAPI class, the check for self.JSON ensures that the API was atleast called.

waybackpy/availability_api.py

@@ -31,10 +31,16 @@ class WaybackMachineAvailabilityAPI:
         self.headers = {"User-Agent": self.user_agent}
         self.payload = {"url": "{url}".format(url=self.url)}
         self.endpoint = "https://archive.org/wayback/available"
+        self.JSON = None
 
     def unix_timestamp_to_wayback_timestamp(self, unix_timestamp):
         return datetime.utcfromtimestamp(int(unix_timestamp)).strftime("%Y%m%d%H%M%S")
 
+    def __str__(self):
+        if not self.JSON:
+            return None
+        return self.archive_url
+
     def json(self):
         self.request_url = full_url(self.endpoint, self.payload)
         self.response = requests.get(self.request_url, self.headers)