Does anyone have any advice on diagnosing/solving the following error:

Traceback (most recent call last):
  File "/usr/local/freesurfer/bin/mri_label_fusion", line 11, in <module>
    from freesurfer.algorithm import maxflow, performFrontPropagation3D
ModuleNotFoundError: No module named 'freesurfer.algorithm'
set: No match.

I am using infant FreeSurfer, so it is possible that this error is specific to that. I've searched through the FreeSurfer listservs and can't find any mention of this error.

I am using the stable release of FreeSurfer: freesurfer-Linux-centos6_x86_64-stable-pub-v6.0.0.tar.gz on RHEL 7.