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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 read_sheets(archive):
 """Read worksheet titles and ids for a workbook"""

    xml_source = archive.read(ARC_WORKBOOK)
    tree = fromstring(xml_source)
    for element in safe_iterator(tree, '{%s}sheet' % SHEET_MAIN_NS):
        attrib = element.attrib
        attrib['id'] = attrib["{%s}id" % REL_NS]
        del attrib["{%s}id" % REL_NS]
        if attrib['id']:
            yield attrib