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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 assign_variable_names(self):
 """ Assign default names to all variables. :return: None """


        for var in self._variables:
            if isinstance(var, SimStackVariable):
                if var.name is not None:
                    continue
                if var.ident.startswith('iarg'):
                    var.name = 'arg_%x' % var.offset
                else:
                    var.name = 's_%x' % (-var.offset)
                    # var.name = var.ident
            elif isinstance(var, SimRegisterVariable):
                if var.name is not None:
                    continue
                var.name = var.ident