Terminal output from running `gh-issues-import.py`

gistfile1.txt

$ python3 gh-issues-import.py 
Traceback (most recent call last):
  File "gh-issues-import.py", line 154, in <module>
    main()
  File "gh-issues-import.py", line 142, in main
    import_labels(labels)
  File "gh-issues-import.py", line 78, in import_labels
    req.add_header("Authorization", "Basic " + base64.urlsafe_b64encode("%s:%s" % (username, password)))
  File "/usr/lib/python3.2/base64.py", line 119, in urlsafe_b64encode
    return b64encode(s, b'-_')
  File "/usr/lib/python3.2/base64.py", line 56, in b64encode
    raise TypeError("expected bytes, not %s" % s.__class__.__name__)
TypeError: expected bytes, not str