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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _get_user_provided_overrides(modules):
 """Load user-provided config overrides. :param modules: stack modules to lookup in user overrides yaml file. :returns: overrides dictionary. """

    overrides = os.path.join(os.environ['JUJU_CHARM_DIR'],
                             'hardening.yaml')
    if os.path.exists(overrides):
        log("Found user-provided config overrides file '%s'" %
            (overrides), level=DEBUG)
        settings = yaml.safe_load(open(overrides))
        if settings and settings.get(modules):
            log("Applying '%s' overrides" % (modules), level=DEBUG)
            return settings.get(modules)

        log("No overrides found for '%s'" % (modules), level=DEBUG)
    else:
        log("No hardening config overrides file '%s' found in charm "
            "root dir" % (overrides), level=DEBUG)

    return {}