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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 _exclude_ss_bonded_cysteines(self):
 """ Pre-compute ss bonds to discard cystines for H-adding. """

        
        ss_bonds =  self.nh_structure.search_ss_bonds()
        for cys_pair in ss_bonds:
            cys1,  cys2 = cys_pair
            
            cys1.resname = 'CYX'
            cys2.resname = 'CYX'