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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_content_types(archive):
 """Read content types."""

    xml_source = archive.read(ARC_CONTENT_TYPES)
    root = fromstring(xml_source)
    contents_root = root.findall('{%s}Override' % CONTYPES_NS)
    for type in contents_root:
        yield type.get('ContentType'), type.get('PartName')