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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 validate(self):
 """Validate workflow object. This method currently validates the workflow object with the use of cwltool. It writes the workflow to a tmp CWL file, reads it, validates it and removes the tmp file again. By default, the workflow is written to file using absolute paths to the steps. """

        # define tmpfile
        (fd, tmpfile) = tempfile.mkstemp()
        os.close(fd)
        try:
            # save workflow object to tmpfile,
            # do not recursively call validate function
            self.save(tmpfile, mode='abs', validate=False)
            # load workflow from tmpfile
            document_loader, processobj, metadata, uri = load_cwl(tmpfile)
        finally:
            # cleanup tmpfile
            os.remove(tmpfile)