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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_key_value(self, event, event_type):
 """Get the key value."""

        if event_type == 10:
            value = 1
        elif event_type == 11:
            value = 0
        elif event_type == 12:
            value = self._get_flag_value(event)
        else:
            value = -1
        return value