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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 get_content_type(ct_name):
 """ A helper function that returns ContentType object based on its slugified verbose_name_plural. Results of this function is cached to improve performance. :Parameters: - `ct_name`: Slugified verbose_name_plural of the target model. :Exceptions: - `Http404`: if no matching ContentType is found """

    try:
        ct = CONTENT_TYPE_MAPPING[ct_name]
    except KeyError:
        for model in models.get_models():
            if ct_name == slugify(model._meta.verbose_name_plural):
                ct = ContentType.objects.get_for_model(model)
                CONTENT_TYPE_MAPPING[ct_name] = ct
                break
        else:
            raise Http404
    return ct