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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 relaxNGNewMemParserCtxt(buffer, size):
 """Create an XML RelaxNGs parse context for that memory buffer expected to contain an XML RelaxNGs file. """

    ret = libxml2mod.xmlRelaxNGNewMemParserCtxt(buffer, size)
    if ret is None:raise parserError('xmlRelaxNGNewMemParserCtxt() failed')
    return relaxNgParserCtxt(_obj=ret)