Fixed #19132 -- Added example for creating custom lazy function

Thanks flagzeta@yahoo.it for the report and Luke Plant for his
expert assistance.

docs/topics/i18n/translation.txt

@@ -427,6 +427,24 @@ In this case, the lazy translations in ``result`` will only be converted to
 strings when ``result`` itself is used in a string (usually at template
 rendering time).
 
+Other uses of lazy in delayed translations
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+For any other case where you would like to delay the translation, but have to
+pass the translatable string as argument to another function, you can wrap
+this function inside a lazy call yourself. For example::
+
+    from django.utils import six  # Python 3 compatibility
+    from django.utils.functional import lazy
+    from django.utils.safestring import mark_safe
+    from django.utils.translation import ugettext_lazy as _
+
+    mark_safe_lazy = lazy(mark_safe, six.text_type)
+
+And then later::
+
+    lazy_string = mark_safe_lazy(_("<p>My <strong>string!</strong></p>"))
+
 Localized names of languages
 ----------------------------