bcbio-nextgen: Encoding errors with CIVIC svprioritize and IPython distributed tasks

A typical error, which occurs somehow inside bedtools, is like this:

Traceback (most recent call last):
  File "/opt/bcbio/anaconda/lib/python3.6/site-packages/bcbio/distributed/ipythontasks.py", line 52, in _setup_logging
    yield config
  File "/opt/bcbio/anaconda/lib/python3.6/site-packages/bcbio/distributed/ipythontasks.py", line 447, in detect_sv
    return ipython.zip_args(apply(structural.detect_sv, *args))
  File "/opt/bcbio/anaconda/lib/python3.6/site-packages/bcbio/distributed/ipythontasks.py", line 80, in apply
    return object(*args, **kwargs)
  File "/opt/bcbio/anaconda/lib/python3.6/site-packages/bcbio/structural/__init__.py", line 205, in detect_sv
    for svdata in caller_fn(items):
  File "/opt/bcbio/anaconda/lib/python3.6/site-packages/bcbio/structural/cnvkit.py", line 57, in run
    return _cnvkit_by_type(items, background)
  File "/opt/bcbio/anaconda/lib/python3.6/site-packages/bcbio/structural/cnvkit.py", line 67, in _cnvkit_by_type
    return _run_cnvkit_single(items[0])
  File "/opt/bcbio/anaconda/lib/python3.6/site-packages/bcbio/structural/cnvkit.py", line 110, in _run_cnvkit_single
    return _associate_cnvkit_out(ckouts, [data])
  File "/opt/bcbio/anaconda/lib/python3.6/site-packages/bcbio/structural/cnvkit.py", line 90, in _associate_cnvkit_out
    ckout = _add_plots_to_output(ckout, data)
  File "/opt/bcbio/anaconda/lib/python3.6/site-packages/bcbio/structural/cnvkit.py", line 640, in _add_plots_to_output
    scatter = _add_scatter_plot(out, data)
  File "/opt/bcbio/anaconda/lib/python3.6/site-packages/bcbio/structural/cnvkit.py", line 710, in _add_scatter_plot
    priority_bed = plot._prioritize_plot_regions(pybedtools.BedTool(priority_bed), data, os.path.dirname(out_file))
  File "/opt/bcbio/anaconda/lib/python3.6/site-packages/bcbio/structural/plot.py", line 91, in _prioritize_plot_regions
    for r in region_bt:
  File "pybedtools/cbedtools.pyx", line 754, in pybedtools.cbedtools.IntervalIterator.__next__
  File "/opt/bcbio/anaconda/lib/python3.6/encodings/ascii.py", line 26, in decode
    return codecs.ascii_decode(input, self.errors)[0]
UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 749: ordinal not in range(128)

Note that this only occurs when running distributed. Running local (-t local) even with multiprocessing, won’t trigger this error. Testing this locally doesn’t yield problems either.