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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 hal(root, 
            apiname=None, 
            default_curie=None,
            auth=None, 
            headers=None, 
            session=None,
            ):
        '''Create a HALNavigator'''
        root = utils.fix_scheme(root)
        halnav = HALNavigator(
            link=Link(uri=root),
            core=APICore(
                root=root,
                nav_class=HALNavigator,
                apiname=apiname,
                default_curie=default_curie,
                session=session,
            )
        )
        if auth:
            halnav.authenticate(auth)
        halnav.headers.update(DEFAULT_HEADERS)
        if headers is not None:
            halnav.headers.update(headers)
        return halnav