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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 htmlCreatePushParser(SAX, chunk, size, URI):
 """Create a progressive HTML parser context to build either an event flow if the SAX object is not None, or a DOM tree otherwise. """

    ret = libxml2mod.htmlCreatePushParser(SAX, chunk, size, URI)
    if ret is None:raise parserError('htmlCreatePushParser() failed')
    return parserCtxt(_obj=ret)