def make_extended_structure(AA_chain):
    '''Place a sequence of amino acids into a peptide in the extended
    conformation. The argument AA_chain holds the sequence of amino
    acids to be used.'''
    geo = geometry(AA_chain[0])
    struc=initialize_res(geo)
    
    for i in range(1,len(AA_chain)): 
        AA = AA_chain[i]
        geo = geometry(AA)
        add_residue(struc, geo)

    return struc
def make_extended_structure ( AA_chain ) : geo = geometry ( AA_chain [ 0 ] ) struc = initialize_res ( geo ) for i in range ( 1 , len ( AA_chain ) ) : AA = AA_chain [ i ] geo = geometry ( AA ) add_residue ( struc , geo ) return struc
Place a sequence of amino acids into a peptide in the extended
    conformation. The argument AA_chain holds the sequence of amino
    acids to be used.