Typo Fix (#3087)

Author: pspoffice

boto3/docs/resource.py

@@ -131,7 +131,7 @@ def _add_identifiers(self, section):
                 resource_type='Identifiers',
                 description=(
                     'Identifiers are properties of a resource that are '
-                    'set upon instantation of the resource.'),
+                    'set upon instantiation of the resource.'),
                 intro_link='identifiers_attributes_intro')
         for identifier in identifiers:
             identifier_section = section.add_new_section(identifier.name)