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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 validate_onset(reference_event, estimated_event, t_collar=0.200):
 """Validate estimated event based on event onset Parameters reference_event : dict Reference event. estimated_event: dict Estimated event. t_collar : float > 0, seconds Time collar with which the estimated onset has to be in order to be consider valid estimation. Default value 0.2 Returns ------- bool """


        # Detect field naming style used and validate onset
        if 'event_onset' in reference_event and 'event_onset' in estimated_event:
            return math.fabs(reference_event['event_onset'] - estimated_event['event_onset']) <= t_collar

        elif 'onset' in reference_event and 'onset' in estimated_event:
            return math.fabs(reference_event['onset'] - estimated_event['onset']) <= t_collar