Multiple incompatible subclass instances of TerminalInteractiveShell

Hello,

from my ipyparallel application I get this error:

Multiple incompatible subclass instances of TerminalInteractiveShell are being created.

(complete traceback below)

System is Arch Linux, ipython-ipyparallel 6.0.2.

The ipcluster was started in the same directory in which also the client was started.

What I do is basically:

rc = ipp.Client()
lview = rc.load_balanced_view()
dview = rc[:]
dview.use_cloudpickle()
dview.execute("import numpy as np")
dview.execute("import RBF")
dview.push({"SeparatedConsistent" : SeparatedConsistent})

# BFs is a list of functions
separated = lview.map(lambda x: SeparatedConsistent(x, in_mesh, in_vals), BFs)
separated.wait()

# This works, as a serial alternative:
# separated = [SeparatedConsistent(x, in_mesh, in_vals) for x in BFs]

# The exception happens here
ax1.semilogy(ms, [i.RMSE(func, test_mesh) for i in separated], "--", label = "RMSE")


Sorry for being able to present only applications fragments.

What could cause this error message? Google turned up nothing helpful.

Best Thanks,
Florian


Traceback (most recent call last):
  File "parallel.py", line 57, in <module>
    main()
  File "parallel.py", line 53, in main
    plot_shape_parameters()
  File "parallel.py", line 26, in plot_shape_parameters
    ax1.semilogy(ms, [i.RMSE(func, test_mesh) for i in separated], "--", label = "RMSE")
  File "parallel.py", line 26, in <listcomp>
    ax1.semilogy(ms, [i.RMSE(func, test_mesh) for i in separated], "--", label = "RMSE")
  File "/usr/lib/python3.6/site-packages/ipyparallel/client/asyncresult.py", line 673, in __iter__
    for r in it():
  File "/usr/lib/python3.6/site-packages/ipyparallel/client/asyncresult.py", line 692, in _ordered_iter
    rlist = self.get(0)
  File "/usr/lib/python3.6/site-packages/ipyparallel/client/asyncresult.py", line 167, in get
    raise self.exception()
  File "/usr/lib/python3.6/site-packages/ipyparallel/client/asyncresult.py", line 226, in _resolve_result
    results = error.collect_exceptions(results, self._fname)
  File "/usr/lib/python3.6/site-packages/ipyparallel/error.py", line 233, in collect_exceptions
    raise e
  File "/usr/lib/python3.6/site-packages/ipyparallel/error.py", line 231, in collect_exceptions
    raise CompositeError(msg, elist)
ipyparallel.error.CompositeError: one or more exceptions from call to method: <lambda>
[0:apply]: MultipleInstanceError: Multiple incompatible subclass instances of TerminalInteractiveShell are being created.
[2:apply]: MultipleInstanceError: Multiple incompatible subclass instances of TerminalInteractiveShell are being created.
[3:apply]: MultipleInstanceError: Multiple incompatible subclass instances of TerminalInteractiveShell are being created.
[1:apply]: MultipleInstanceError: Multiple incompatible subclass instances of TerminalInteractiveShell are being created.
.... 46 more exceptions ...