Import error in exporter.py - fastimport.helpers

When exporting bzr using fastimport, I have discovered an error:
bzr: ERROR: exceptions.ImportError: cannot import name binary_stream

Traceback (most recent call last):
  File "/usr/lib/python2.7/site-packages/bzrlib/commands.py", line 930, in exception_to_return_code
    return the_callable(*args, **kwargs)
  File "/usr/lib/python2.7/site-packages/bzrlib/commands.py", line 1121, in run_bzr
    ret = run(*run_argv)
  File "/usr/lib/python2.7/site-packages/bzrlib/commands.py", line 673, in run_argv_aliases
    return self.run(**all_cmd_args)
  File "/usr/lib/python2.7/site-packages/bzrlib/commands.py", line 697, in run
    return self._operation.run_simple(*args, **kwargs)
  File "/usr/lib/python2.7/site-packages/bzrlib/cleanup.py", line 136, in run_simple
    self.cleanups, self.func, *args, **kwargs)
  File "/usr/lib/python2.7/site-packages/bzrlib/cleanup.py", line 166, in _do_with_cleanups
    result = func(*args, **kwargs)
  File "/usr/lib/python2.7/site-packages/bzrlib/plugins/fastimport/cmds.py", line 679, in run
    from bzrlib.plugins.fastimport import exporter
  File "/usr/lib/python2.7/site-packages/bzrlib/plugins/fastimport/exporter.py", line 67, in <module>
    from fastimport.helpers import (
ImportError: cannot import name binary_stream

The relivent lines of code are in bzrlib/plugins/fastimport/exporter.py:
from fastimport.helpers import (
    binary_stream,
    single_plural,
    )

Problem:
binary_stream and single_pural where removed from lb:python-fastimport in revition 327. Relevint commit message:
revno: 327
committer: Jelmer Vernooij <email address hidden>
timestamp: Sat 2014-03-01 15:26:41 +0000
message:
  Remove unused helper

This makes it imposible for me to import/export bzr repos to git using git-bzr-ng.