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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 sort_vid_split(vs):
 """ Split a valid variable string into its variable sort and id. Examples: ('h', '3') ('ref-ind', '12') """

    match = var_re.match(vs)
    if match is None:
        raise ValueError('Invalid variable string: {}'.format(str(vs)))
    else:
        return match.groups()