Better explain the lazy import filter

Author: AA-Turner

peps/pep-0810.rst

@@ -322,11 +322,14 @@ If the global lazy imports flag is set to "disabled", no *potentially lazy*
 import is ever imported lazily, and the behavior is equivalent to a regular
 import statement: the import is *eager* (as if the lazy keyword was not used).
 
-For a *potentially lazy* import, the lazy imports filter (if set) is called
-with the name of the module doing the import, the name of the module being
-imported, and (if applicable) the fromlist. If the lazy import filter returns
-``True``, the *potentially lazy* import becomes a lazy import. Otherwise, the
-import is *not* lazy, and the normal (eager) import continues.
+Finally, the application may use a custom filter function on all *potentially
+lazy* imports to determine if they should be lazy or not.
+If a filter function is set, it will be called with the name of the module
+doing the import, the name of the module being imported, and (if applicable)
+the fromlist.
+An import remains lazy only if the filter function returns ``True``.
+
+If no lazy import filter is set, all *potentially lazy* imports are lazy.
 
 Lazy import mechanism
 ---------------------