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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 post_processor_population_displacement_function( hazard=None, classification=None, hazard_class=None, population=None):
 """Private function used in the displacement postprocessor. :param hazard: The hazard to use. :type hazard: str :param classification: The hazard classification to use. :type classification: str :param hazard_class: The hazard class of the feature. :type hazard_class: str :param population: We don't use this value here. It's only used for condition for the postprocessor to run. :type population: float, int :return: The displacement ratio for a given hazard class. :rtype: float """

    _ = population  # NOQA

    return get_displacement_rate(hazard, classification, hazard_class)