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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 _find_secondary_anchors(self, residue, heavy_atom, anchor):
 """ Searches through the bond network for atoms bound to the anchor. Returns a secondary and tertiary anchors. Example, for CA, returns C and O. """

        
        for secondary in self.bonds[residue][anchor.name][1]:
            for tertiary in self.bonds[residue][secondary.name][1]:
                if (tertiary.name != heavy_atom.name 
                    and tertiary.name != anchor.name):
                    
                    return (secondary,  tertiary)
        
        return None