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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_context(request, context=None):
 """Returns common context data for network topology views."""

    if context is None:
        context = {}

    network_config = getattr(settings, 'OPENSTACK_NEUTRON_NETWORK', {})

    context['launch_instance_allowed'] = policy.check(
        (("compute", "os_compute_api:servers:create"),), request)
    context['instance_quota_exceeded'] = _quota_exceeded(request, 'instances')
    context['create_network_allowed'] = policy.check(
        (("network", "create_network"),), request)
    context['network_quota_exceeded'] = _quota_exceeded(request, 'network')
    context['create_router_allowed'] = (
        network_config.get('enable_router', True) and
        policy.check((("network", "create_router"),), request))
    context['router_quota_exceeded'] = _quota_exceeded(request, 'router')
    context['console_type'] = getattr(settings, 'CONSOLE_TYPE', 'AUTO')
    context['show_ng_launch'] = (
        base.is_service_enabled(request, 'compute') and
        getattr(settings, 'LAUNCH_INSTANCE_NG_ENABLED', True))
    context['show_legacy_launch'] = (
        base.is_service_enabled(request, 'compute') and
        getattr(settings, 'LAUNCH_INSTANCE_LEGACY_ENABLED', False))
    return context