touch up comments again

pydra/utils/hash.py

@@ -242,12 +242,13 @@ def calc_hash(first: ty.Optional[bytes] = None) -> Hash:
                 h.update(chunk)
             return Hash(h.digest())
 
-        # Read the first item of the bytes_repr iterator and check to see whether it returns
+        # Read the first item of the bytes_repr iterator and check to see whether it yields
         # a "cache-key" tuple instead of a bytes chunk for the type of the object to be cached
-        # (e.g. fileformats.core.FileSet objects). If it does use that key to check the
-        # persistent cache for a precomputed hash and return it if it is, otherwise
-        # calculate the hash and store it in the persistent cache with that hash of
-        # that key (not to be confused with the hash of the object that is saved/retrieved).
+        # (e.g. file-system path + mtime for fileformats.core.FileSet objects). If it
+        # does, use that key to check the persistent cache for a precomputed hash and
+        # return it if it is, otherwise calculate the hash and store it in the persistent
+        # cache with that hash of that key (not to be confused with the hash of the
+        # object that is saved/retrieved).
         first = next(bytes_it)
         if isinstance(first, tuple):
             tp = type(obj)