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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 children( record, index, key='refs', stop_types=STOP_TYPES ):
 """Retrieve children records for given record"""

    result = []
    for ref in record.get( key,[]):
        try:
            record = index[ref]
        except KeyError, err:
            #print 'No record for %s address %s in %s'%(key, ref, record['address'] )
            pass # happens when an unreachable references a reachable that has been compressed out...
        else:
            if record['type'] not in stop_types:
                result.append(  record  )
    return result