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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 _getarglimb(self, arg, n):
 """Get the nth limb of the given wire. Returns '0' when the wire does not have sufficient limbs. """

        return '{vn}[{n}]'.format(vn=self.varname[arg], n=n) if arg.bitwidth > 64*n else '0'