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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 _handle_start_center(self, attrs):
 """ Handle opening center element :param attrs: Attributes of the element :type attrs: Dict """

        center_lat = attrs.get("lat")
        center_lon = attrs.get("lon")
        if center_lat is None or center_lon is None:
            raise ValueError("Unable to get lat or lon of way center.")
        self._curr["center_lat"] = Decimal(center_lat)
        self._curr["center_lon"] = Decimal(center_lon)