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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 _get_clstr_outfile(self):
 """Returns the absolute path to the clstr outfile"""

        if self.Parameters['-o'].isOn():
            return ''.join([self.Parameters['-o'].Value, '.clstr'])
        else:
            raise ValueError, "No output file specified"