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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 sum_stats(stats_data):
 """ Summarize the bounces, complaints, delivery attempts and rejects from a list of datapoints. """

    t_bounces = 0
    t_complaints = 0
    t_delivery_attempts = 0
    t_rejects = 0
    for dp in stats_data:
        t_bounces += int(dp['Bounces'])
        t_complaints += int(dp['Complaints'])
        t_delivery_attempts += int(dp['DeliveryAttempts'])
        t_rejects += int(dp['Rejects'])

    return {
        'Bounces': t_bounces,
        'Complaints': t_complaints,
        'DeliveryAttempts': t_delivery_attempts,
        'Rejects': t_rejects,
    }