Update README.md

Co-authored-by: Terrell Russell <terrellrussell@gmail.com>

Author: d-w-moore

README.md

@@ -462,8 +462,8 @@ given logical path.  For an example of this, jump forward to [working with data
 Note that a `replica_sort_function` option exists in the `iRODSDataObject` constructor and in
 `<session_object>.data_objects.get`. If `replica_sort_function` is not specified, the replicas
 list contained in the returned object will be sorted according to replica number
-(REPLICA_NUMBER_SORT_KEY_FN) in PRC < v4 or by general fitness to be considered as a
-current data copy (REPLICA_FITNESS_SORT_KEY_FN).  in PRC >= v4.  For those definitions, see `irods/data_object.py`.
+(REPLICA_NUMBER_SORT_KEY_FN) in PRC < v4 or by general fitness to be considered a
+good representation of that object (REPLICA_FITNESS_SORT_KEY_FN) in PRC >= v4.  For those definitions, see `irods/data_object.py`.
 
 Working with collections (directories)
 --------------------------------------