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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 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