File "/usr/lib/python2.7/dist-packages/bzrlib/commands.py", line 695, in run
    return self._operation.run_simple(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/cleanup.py", line 136, in run_simple
    self.cleanups, self.func, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/cleanup.py", line 166, in _do_with_cleanups
    result = func(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/builtins.py", line 3660, in run
    lossy=lossy)
  File "/usr/lib/python2.7/dist-packages/bzrlib/decorators.py", line 218, in write_locked
    result = unbound(self, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/workingtree_4.py", line 213, in commit
    result = WorkingTree.commit(self, message, revprops, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/decorators.py", line 218, in write_locked
    result = unbound(self, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/mutabletree.py", line 203, in commit
    possible_master_transports)
  File "/usr/lib/python2.7/dist-packages/bzrlib/commit.py", line 187, in update_revprops
    possible_master_transports)
  File "/usr/lib/python2.7/dist-packages/bzrlib/branch.py", line 282, in _get_nick
    master = self.get_master_branch(possible_transports)
  File "/usr/lib/python2.7/dist-packages/bzrlib/decorators.py", line 155, in read_locked
    result = unbound(self, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/bzrlib/branch.py", line 2674, in get_master_branch
    possible_transports)
  File "/usr/lib/python2.7/dist-packages/bzrlib/branch.py", line 2683, in _get_master_branch
    possible_transports=possible_transports)
  File "/usr/lib/python2.7/dist-packages/bzrlib/branch.py", line 185, in open
    possible_transports=possible_transports, _unsupported=_unsupported)
  File "/usr/lib/python2.7/dist-packages/bzrlib/controldir.py", line 685, in open
    t = _mod_transport.get_transport(base, possible_transports)
  File "/usr/lib/python2.7/dist-packages/bzrlib/transport/__init__.py", line 1679, in get_transport
    return get_transport_from_url(location_to_url(base), possible_transports)
  File "/usr/lib/python2.7/dist-packages/bzrlib/transport/__init__.py", line 1654, in get_transport_from_url
    transport, last_err = _try_transport_factories(url, factory_list)
  File "/usr/lib/python2.7/dist-packages/bzrlib/transport/__init__.py", line 1686, in _try_transport_factories
    return factory.get_obj()(base), None
  File "/usr/lib/python2.7/dist-packages/bzrlib/transport/http/_urllib.py", line 48, in __init__
    report_activity=self._report_activity, ca_certs=ca_certs)
TypeError: __init__() got an unexpected keyword argument 'ca_certs'