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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 postActivate_(self):
 """Create temporary file for image dumps and the analyzer itself """

        self.tmpfile = os.path.join(constant.tmpdir,"valkka-"+str(os.getpid())) # e.g. "/tmp/valkka-10968" 
        self.analyzer = ExternalDetector(
            executable = self.executable,
            image_dimensions = self.image_dimensions,
            tmpfile = self.tmpfile
            )