NOE script mode - setting up the spin systems

The backbone amide nitrogen sequence is extracted from a PDB file using the same commands as the relaxation curve-fitting script (Chapter 5. The command

[firstnumber=6]
# Load the sequence from a PDB file.
structure.read_pdb('Ap4Aase_new_3.pdb')

will load the PDB file Ap4Aase_new_3.pdb into relax. Then the following commands will generate both the backbone amide and tryptophan indole ¹⁵N spins

[firstnumber=8]
structure.load_spins(spin_id='@N')
structure.load_spins(spin_id='@NE1')