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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 tag_sidechain_dihedrals(self, force=False):
 """Tags each monomer with side-chain dihedral angles force: bool, optional If `True` the tag will be run even if `Residues` are already tagged. """

        tagged = ['chi_angles' in x.tags.keys() for x in self._monomers]
        if (not all(tagged)) or force:
            for monomer in self._monomers:
                chi_angles = measure_sidechain_torsion_angles(
                    monomer, verbose=False)
                monomer.tags['chi_angles'] = chi_angles
        return