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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 event_filter_type(self, event_filter_type):
 """Sets the event_filter_type of this Dashboard. How charts belonging to this dashboard should display events. BYCHART is default if unspecified # noqa: E501 :param event_filter_type: The event_filter_type of this Dashboard. # noqa: E501 :type: str """

        allowed_values = ["BYCHART", "AUTOMATIC", "ALL", "NONE", "BYDASHBOARD", "BYCHARTANDDASHBOARD"]  # noqa: E501
        if event_filter_type not in allowed_values:
            raise ValueError(
                "Invalid value for `event_filter_type` ({0}), must be one of {1}"  # noqa: E501
                .format(event_filter_type, allowed_values)
            )

        self._event_filter_type = event_filter_type