docs: def getAtomLinesForResidueInRosettaStructure(self, resid):
          '''We assume a Rosetta-generated structure where residues are uniquely identified by number.'''
          lines = [line for line in self.lines if line[0:4] == "ATOM" and resid == int(line[22:27])]
          if not lines:
              #print('Failed searching for residue %d.' % resid)
              #print("".join([line for line in self.lines if line[0:4] == "ATOM"]))
              raise Exception("Could not find the ATOM/HETATM line corresponding to residue '%(resid)s'." % vars())
          return lines