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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 service_present(name, service_type, description=None,
                    profile=None, **connection_args):
    '''
    Ensure service present in Keystone catalog

    name
        The name of the service

    service_type
        The type of Openstack Service

    description (optional)
        Description of the service
    '''
    ret = {'name': name,
           'changes': {},
           'result': True,
           'comment': 'Service "{0}" already exists'.format(name)}

    # Check if service is already present
    role = __salt__['keystone.service_get'](name=name,
                                            profile=profile,
                                            **connection_args)

    if 'Error' not in role:
        return ret
    else:
        if __opts__.get('test'):
            ret['result'] = None
            ret['comment'] = 'Service "{0}" will be added'.format(name)
            return ret
        # Create service
        __salt__['keystone.service_create'](name, service_type,
                                            description,
                                            profile=profile,
                                            **connection_args)
        ret['comment'] = 'Service "{0}" has been added'.format(name)
        ret['changes']['Service'] = 'Created'

    return ret