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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 _init_default_values(self):
 """Set default initial values The default values are hard-coded for backwards compatibility and for several functionalities in dclab. """

        # Do not filter out invalid event values
        self["filtering"]["remove invalid events"] = False
        # Enable filters switch is mandatory
        self["filtering"]["enable filters"] = True
        # Limit events integer to downsample output data
        self["filtering"]["limit events"] = 0
        # Polygon filter list
        self["filtering"]["polygon filters"] = []
        # Defaults to no hierarchy parent
        self["filtering"]["hierarchy parent"] = "none"
        # Check for missing min/max values and set them to zero
        for item in dfn.scalar_feature_names:
            appends = [" min", " max"]
            for a in appends:
                self["filtering"][item + a] = 0