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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 set_euk_hmm(self, args):
        'Set the hmm used by graftM to cross check for euks.'
        if hasattr(args, 'euk_hmm_file'):
            pass
        elif not hasattr(args, 'euk_hmm_file'):
            # set to path based on the location of bin/graftM, which has
            # a more stable relative path to the HMM when installed through
            # pip.
            setattr(args, 'euk_hmm_file', os.path.join(os.path.dirname(inspect.stack()[-1][1]),'..','share', '18S.hmm'))
        else:
            raise Exception('Programming Error: setting the euk HMM')