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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 openstack(request):
 """Context processor necessary for OpenStack Dashboard functionality. The following variables are added to the request context: ``authorized_tenants`` A list of tenant objects which the current user has access to. ``regions`` A dictionary containing information about region support, the current region, and available regions. """

    context = {}

    # Auth/Keystone context
    context.setdefault('authorized_tenants', [])
    if request.user.is_authenticated:
        context['authorized_tenants'] = [
            tenant for tenant in
            request.user.authorized_tenants if tenant.enabled]

    # Region context/support
    available_regions = getattr(settings, 'AVAILABLE_REGIONS', [])
    regions = {'support': len(available_regions) > 1,
               'current': {'endpoint': request.session.get('region_endpoint'),
                           'name': request.session.get('region_name')},
               'available': [{'endpoint': region[0], 'name':region[1]} for
                             region in available_regions]}

    # K2K Federation Service Providers context/support
    available_providers = request.session.get('keystone_providers', [])
    if available_providers:
        provider_id = request.session.get('keystone_provider_id', None)
        provider_name = None
        for provider in available_providers:
            if provider['id'] == provider_id:
                provider_name = provider.get('name')

        keystone_providers = {
            'support': len(available_providers) > 1,
            'current': {
                'name': provider_name,
                'id': provider_id
            },
            'available': [
                {'name': keystone_provider['name'],
                 'id': keystone_provider['id']}
                for keystone_provider in available_providers]
        }
    else:
        keystone_providers = {'support': False}

    context['keystone_providers'] = keystone_providers
    context['regions'] = regions

    # Adding webroot access
    context['WEBROOT'] = getattr(settings, "WEBROOT", "/")

    user_menu_links = getattr(settings, "USER_MENU_LINKS", [])

    if not getattr(settings, "SHOW_KEYSTONE_V2_RC", False):
        user_menu_links = [
            link for link in user_menu_links
            if link['url'] != 'horizon:project:api_access:openrcv2']

    context['USER_MENU_LINKS'] = user_menu_links

    # Adding profiler support flag
    profiler_settings = getattr(settings, 'OPENSTACK_PROFILER', {})
    profiler_enabled = profiler_settings.get('enabled', False)
    context['profiler_enabled'] = profiler_enabled
    if profiler_enabled and 'profile_page' in request.COOKIES:
        index_view_id = request.META.get(profiler.ROOT_HEADER, '')
        hmac_keys = profiler_settings.get('keys', [])
        context['x_trace_info'] = profiler.update_trace_headers(
            hmac_keys, parent_id=index_view_id)

    context['JS_CATALOG'] = get_js_catalog(conf)

    return context