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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 implied_feature (implicit_value):
 """ Returns the implicit feature associated with the given implicit value. """

    assert isinstance(implicit_value, basestring)
    components = implicit_value.split('-')

    if components[0] not in __implicit_features:
        raise InvalidValue ("'%s' is not a value of an implicit feature" % implicit_value)

    return __implicit_features[components[0]]