MayaviClient not compatible with Python 3

[divico]

It seems that MayaviClient can't be used with python 3. Running

from fipy import *
mesh = Grid3D(nx=50, ny=100, nz=10, dx=0.1, dy=0.01, dz=0.1)
x, y, z = mesh.cellCenters
xyzVar = CellVariable(mesh=mesh, name=r"x y z", value=x * y * z)
k = Variable(name="k", value=0.)
viewer = MayaviClient(vars=numerix.sin(k * xyzVar),
                     limits={'ymin': 0.1, 'ymax': 0.9},
                     datamin=-0.9, datamax=2.0,
                     title="MayaviClient test")

from builtins import range
for kval in range(10):
     k.setValue(kval)
     viewer.plot()
viewer._promptForOpinion()

gives the following error

NameError                                 Traceback (most recent call last)
<ipython-input-2-5f5075ddbc20> in <module>
      4 xyzVar = CellVariable(mesh=mesh, name=r"x y z", value=x * y * z)
      5 k = Variable(name="k", value=0.)
----> 6 viewer = MayaviClient(vars=numerix.sin(k * xyzVar),
      7                      limits={'ymin': 0.1, 'ymax': 0.9},
      8                      datamin=-0.9, datamax=2.0,

/usr/lib/python3.8/site-packages/fipy/viewers/mayaviViewer/mayaviClient.py in __init__(self, vars, title, daemon_file, fps, **kwlimits)
     73         AbstractViewer.__init__(self, vars=cell_vars + face_vars, title=title, **kwlimits)
     74 
---> 75         self.plot()
     76 
     77         from pkg_resources import Requirement, resource_filename

/usr/lib/python3.8/site-packages/fipy/viewers/mayaviViewer/mayaviClient.py in plot(self, filename)
    147                 if self.vtkFaceViewer is not None:
    148                     self.vtkFaceViewer.plot(filename=self.vtkfacefname)
--> 149                 lock = file(self.vtklockfname, 'w')
    150                 if filename is not None:
    151                     lock.write(filename)

NameError: name 'file' is not defined

replacing lock = file(self.vtklockfname, 'w') with lock = open(self.vtklockfname, 'w') works.

fipy.__version__ '3.4.1'
mayavi.__version__ '4.7.1'
sys.version_info sys.version_info(major=3, minor=8, micro=2, releaselevel='final', serial=0)

Please let me know if I can do some more testing

Thank you

[guyer]

Thank you for the report. I can reproduce the behavior. Unfortunately, even after fixing 'file' is not defined, which was easy, there are still problems that keep it from working. I'll need to dedicate more time to debuggin.