Check dict before deleting. fix #401

couchpotato/core/plugins/scanner/main.py

@@ -257,6 +257,7 @@ class Scanner(Plugin):
 
         # Cleaning up used
         for identifier in delete_identifiers:
+            if self.path_identifiers.get(identifier):
                 del self.path_identifiers[identifier]
         del delete_identifiers
 
@@ -282,6 +283,7 @@ class Scanner(Plugin):
 
         # Cleaning up used
         for identifier in delete_identifiers:
+            if self.path_identifiers.get(identifier):
                 del self.path_identifiers[identifier]
         del delete_identifiers