text: from stellar_base.builder import Builder
  
  alice_seed = 'SB4675LMYLBWMKENDBAO6ZTVPLI6AISE3VZZDZASUFWW2T4MEGKX7NEI'
  bob_address = 'GCRNOBFLTGLGSYOWCYINZA7JAAAZ5CXMSNM7QUYFYOHHIEZY4R6665MA'
  
  selling_code = 'XLM'
  selling_issuer = None
  
  buying_code = 'XCN'
  buying_issuer = 'GCNY5OXYSY4FKHOPT2SPOQZAOEIGXB5LBYW3HVU3OWSTQITS65M5RCNY'
  
  price = '5.5'  # or price = {'n': 55, 'd': 10}
  amount = '12.5'
  
  builder = Builder(secret=alice_seed, horizon_uri='https://horizon-testnet.stellar.org') \
               .append_manage_offer_op(selling_code, selling_issuer, buying_code, \
                buying_issuer, amount, price)
  
  builder.sign()
  builder.submit()