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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 _suffix(self):
 """Return appropriate suffix for alignment file"""

        _output_formats={'GCG':'.msf',
                        'GDE':'.gde',
                        'PHYLIP':'.phy',
                        'PIR':'.pir',
                        'NEXUS':'.nxs'}

        if self.Parameters['-output'].isOn():
            return _output_formats[self.Parameters['-output'].Value]
        else:
            return '.aln'