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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 total(usaf, field='GHI (W/m^2)'):
 """total annual insolation, defaults to GHI."""

    running_total = 0
    usafdata = data(usaf)
    for record in usafdata:
        running_total += float(record[field])
    return running_total/1000.