Fixture in behave is not getting applied

I need a fixture in my behave code so that all the users that I create during testing automatically gets cleaned up. As a result, I added the following code

#test/features/steps/environment.py

@fixture()
def user_cleanup(context):
    # -- SETUP-FIXTURE PART:
    context.users_to_be_cleaned_up = []
    print ("Creating Fixture")
    yield context.users_to_be_cleaned_up
    # -- CLEANUP-FIXTURE PART:
    for userid in context.users_to_be_cleaned_up:
        resp = delete_database_entry("users", userid)
        print (resp)
    context.users_to_be_cleaned_up = []


def before_feature(context, feature):
    if "fixture.user.cleanup" in feature.tags:
        use_fixture(user_cleanup, context)

In my features file, I added the following

@fixture.user.cleanup
Feature: Validating backend from the app side
    
    Scenario Outline: Super Admin has permission to create other users
        Given a set of existing users:
                | user                  | details     |
                | superadmin   | userdetails |             
        When "superadmin" successfully logs in
        Then he can create non-existing "<user>" with "<details>"
            and "<user>" can login successfully with "<details>"

        Examples: User Roles
                | user                | details      |
                | superadmin_1        | user details | 

The idea was to have the test append all the users into context.users_to_be_cleaned_up. But in the test, when I try to append, it says that property users_to_be_cleaned_up is not present in context.

Any idea what I am doing wrong here?