File "/usr/lib/pymodules/python2.7/bzrlib/decorators.py", line 140, in read_locked
    result = unbound(self, *args, **kwargs)
  File "/usr/lib/pymodules/python2.7/bzrlib/branch.py", line 2737, in get_master_branch
    possible_transports=possible_transports)
  File "/usr/lib/pymodules/python2.7/bzrlib/branch.py", line 176, in open
    possible_transports=possible_transports)
  File "/usr/lib/pymodules/python2.7/bzrlib/bzrdir.py", line 717, in open
    return BzrDir.open_from_transport(t, _unsupported=_unsupported)
  File "/usr/lib/pymodules/python2.7/bzrlib/bzrdir.py", line 747, in open_from_transport
    redirected)
  File "/usr/lib/pymodules/python2.7/bzrlib/transport/__init__.py", line 1679, in do_catching_redirections
    return action(transport)
  File "/usr/lib/pymodules/python2.7/bzrlib/bzrdir.py", line 734, in find_format
    transport, _server_formats=_server_formats)
  File "/usr/lib/pymodules/python2.7/bzrlib/controldir.py", line 749, in find_format
    return prober.probe_transport(transport)
  File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/svn/format.py", line 100, in probe_transport
    transport = get_svn_ra_transport(transport)
  File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/svn/transport.py", line 178, in get_svn_ra_transport
    ra_transport = SvnRaTransport(svnbase, credentials=creds)
  File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/svn/errors.py", line 144, in convert
    return unbound(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/svn/transport.py", line 389, in __init__
    self.connections = ConnectionPool(self.svn_url)
  File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/svn/transport.py", line 310, in __init__
    self.auth_baton = create_auth_baton(url)
  File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/svn/auth.py", line 194, in create_auth_baton
    auth_config = SubversionAuthenticationConfig(scheme, host, port, path)
  File "/usr/lib/python2.7/dist-packages/bzrlib/plugins/svn/auth.py", line 55, in __init__
    super(SubversionAuthenticationConfig, self).__init__(file)
  File "/usr/lib/pymodules/python2.7/bzrlib/config.py", line 1292, in __init__
    self._filename = authentication_config_filename()
  File "/usr/lib/pymodules/python2.7/bzrlib/config.py", line 1181, in authentication_config_filename
    return osutils.pathjoin(config_dir(), 'authentication.conf')
  File "/usr/lib/pymodules/python2.7/bzrlib/config.py", line 1132, in config_dir
    base = os.environ.get('BZR_HOME', None)
  File "/usr/lib/python2.7/UserDict.py", line 59, in get
    if key not in self:
RuntimeError: maximum recursion depth exceeded