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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 to_sax(walker, handler):
 """Call SAX-like content handler based on treewalker walker :arg walker: the treewalker to use to walk the tree to convert it :arg handler: SAX handler to use """

    handler.startDocument()
    for prefix, namespace in prefix_mapping.items():
        handler.startPrefixMapping(prefix, namespace)

    for token in walker:
        type = token["type"]
        if type == "Doctype":
            continue
        elif type in ("StartTag", "EmptyTag"):
            attrs = AttributesNSImpl(token["data"],
                                     unadjustForeignAttributes)
            handler.startElementNS((token["namespace"], token["name"]),
                                   token["name"],
                                   attrs)
            if type == "EmptyTag":
                handler.endElementNS((token["namespace"], token["name"]),
                                     token["name"])
        elif type == "EndTag":
            handler.endElementNS((token["namespace"], token["name"]),
                                 token["name"])
        elif type in ("Characters", "SpaceCharacters"):
            handler.characters(token["data"])
        elif type == "Comment":
            pass
        else:
            assert False, "Unknown token type"

    for prefix, namespace in prefix_mapping.items():
        handler.endPrefixMapping(prefix)
    handler.endDocument()