Add note on set_lazy_imports

Author: AA-Turner

peps/pep-0810.rst

@@ -659,6 +659,11 @@ lazy* import is ever imported lazily, the import filter is never called, and
 the behavior is equivalent to a regular ``import`` statement: the import is
 *eager* (as if the lazy keyword was not used).
 
+Python code can run the :func:`!sys.set_lazy_imports` function to override
+the state of the global lazy imports flag inherited from the environment or CLI.
+This is especially useful if an application needs to ensure that all imports
+are evaluated eagerly, via ``sys.set_lazy_imports('disabled')``.
+
 
 Backwards Compatibility
 =======================