Iso Evo will not plot regressions

[nelsiverson]

Traceback (most recent call last):
File "/Users/argonlab/.edm/envs/edm/lib/python3.6/site-packages/traits/trait_notifiers.py", line 342, in call
self.handler(*args)
File "/Users/argonlab/.pychron.0/pychron/pychron/pipeline/editors/results_editor.py", line 361, in _dclicked_fired
result.analysis.show_isotope_evolutions((result.isotope,))
File "/Users/argonlab/.pychron.0/pychron/pychron/processing/analyses/analysis.py", line 783, in show_isotope_evolutions
g = self.get_isotope_evolutions(*args, **kw)
File "/Users/argonlab/.pychron.0/pychron/pychron/processing/analyses/analysis.py", line 780, in get_isotope_evolutions
return show_evolutions_factory(self.record_id, isotopes, **kw)
File "/Users/argonlab/.pychron.0/pychron/pychron/processing/analyses/analysis.py", line 313, in show_evolutions_factory
make_graph(*args)
File "/Users/argonlab/.pychron.0/pychron/pychron/processing/analyses/analysis.py", line 374, in make_graph
color="black",
File "/Users/argonlab/.pychron.0/pychron/pychron/graph/stacked_regression_graph.py", line 23, in new_series
ret = super(StackedRegressionGraph, self).new_series(*args, **kw)
File "/Users/argonlab/.pychron.0/pychron/pychron/graph/regression_graph.py", line 259, in new_series
self._regress(plot, scatter, line)
File "/Users/argonlab/.pychron.0/pychron/pychron/graph/regression_graph.py", line 482, in _regress
r = self._poly_regress(scatter, r, fit)
File "/Users/argonlab/.pychron.0/pychron/pychron/graph/regression_graph.py", line 595, in _poly_regress
r.determine_fit()
TypeError: determine_fit() missing 1 required positional argument: 'fit'