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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 string_match(sf,regex,field=2):
 """ Return the geometry and attributes of a shapefile whose fields match a regular expression given :param sf: shapefile :type sf: shapefile object :regex: regular expression to match :type regex: string :field: field number to be matched with the regex :type field: integer """

    index = []
    shape_records = []
    for rec in enumerate(sf.shapeRecords()):
        m = re.search(regex,rec[1].record[field])
        if m is not None:
            index.append(rec[0])
            shape_records.append(rec[1])
    return index,shape_records