More defensive coding

providers/callsigndata/qrz.py

@@ -129,6 +129,13 @@ class QRZ(APIQueryCallsignDataProvider):
     def qrz_response_to_callsign(callsign, data):
         """Convert the "Callsign" block in QRZ's API response to our own Callsign object."""
 
+        # I have encountered a user passing multiple callsigns to the QRZ lookup function in a way that QRZ actually
+        # does handle, and returns a list of callsign data. If we encounter that, just take the first one, as our own
+        # functions can't deal with multiple calls this way.
+        if isinstance(data, list):
+            data = data[0]
+            callsign = data["call"]
+
         # Get a name
         name = None
         if "name_fmt" in data: