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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 setupParserForBuffer(self, buffer, filename):
 """Setup the parser context to parse a new buffer; Clears any prior contents from the parser context. The buffer parameter must not be None, but the filename parameter can be """

        libxml2mod.xmlSetupParserForBuffer(self._o, buffer, filename)