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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 value_type(value):
 """Classify `value` of bold, color, and underline keys. Parameters value : style value Returns ------- str, {"simple", "lookup", "re_lookup", "interval"} """

    try:
        keys = list(value.keys())
    except AttributeError:
        return "simple"
    if keys in [["lookup"], ["re_lookup"], ["interval"]]:
        return keys[0]
    raise ValueError("Type of `value` could not be determined")