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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 working_dir(val, **kwargs):  # pylint: disable=unused-argument
    '''
    Must be an absolute path
    '''
    try:
        is_abs = os.path.isabs(val)
    except AttributeError:
        is_abs = False
    if not is_abs:
        raise SaltInvocationError('\'{0}\' is not an absolute path'.format(val))
    return val