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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 parse_val(cfg,section,option):
 """extract a single value from .cfg"""

    vals = parse_vals(cfg,section,option)
    if len(vals)==0:
        return ''
    else:
        assert len(vals)==1, (section, option, vals, type(vals))
    return vals[0]