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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 align_nab(tar, ref):
 """Aligns the N-CA and CA-CB vector of the target monomer. Parameters tar: ampal.Residue The residue that will be aligned to the reference. ref: ampal.Residue The reference residue for the alignment. """

    rot_trans_1 = find_transformations(
        tar['N'].array, tar['CA'].array, ref['N'].array, ref['CA'].array)
    apply_trans_rot(tar, *rot_trans_1)
    rot_ang_ca_cb = dihedral(tar['CB'], ref['CA'], ref['N'], ref['CB'])
    tar.rotate(rot_ang_ca_cb, ref['N'].array - ref['CA'].array, ref['N'].array)
    return