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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 keep_max_priority_effects(effects):
 """ Given a list of effects, only keep the ones with the maximum priority effect type. Parameters effects : list of MutationEffect subclasses Returns list of same length or shorter """

    priority_values = map(effect_priority, effects)
    max_priority = max(priority_values)
    return [e for (e, p) in zip(effects, priority_values) if p == max_priority]