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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_perm_model():
 """ Returns the Perm model that is active in this project. """

    try:
        return django_apps.get_model(settings.PERM_MODEL, require_ready=False)
    except ValueError:
        raise ImproperlyConfigured("PERM_MODEL must be of the form 'app_label.model_name'")
    except LookupError:
        raise ImproperlyConfigured(
            "PERM_MODEL refers to model '{}' that has not been installed".format(settings.PERM_MODEL)
        )