Option -r has issues

[fang19911030]

I used the docker to start oyente

When I tried the command: python oyente.py -s xxx.sol -r, there are some errors reported.

Traceback (most recent call last):
  File "/oyente/oyente/oyente.py", line 221, in <module>
    main()
  File "/oyente/oyente/oyente.py", line 216, in main
    exit_code = analyze_solidity()
  File "/oyente/oyente/oyente.py", line 109, in analyze_solidity
    results, exit_code = run_solidity_analysis(inputs)
  File "/oyente/oyente/oyente.py", line 86, in run_solidity_analysis
    result, return_code = symExec.run(disasm_file=inp['disasm_file'], source_map=inp['source_map'], source_file=inp['source'])
  File "/oyente/oyente/symExec.py", line 2458, in run
    ret = detect_vulnerabilities()
  File "/oyente/oyente/symExec.py", line 2290, in detect_vulnerabilities
    rfile.write(str(stop-begin))
NameError: global name 'begin' is not defined