Holoviews: Python 3.8: SyntaxWarning: "is" with a literal. Did you mean "=="?

[rsignell-usgs]

Is it best to stick with Python 3.7 for now? With Python 3.8 I'm getting tons of these annoying syntax error warnings

software version info

python 3.8.6
holoviews 1.13.5

Description of expected behavior and the observed behavior

import holoviews

results in

/srv/conda/envs/notebook/lib/python3.8/site-packages/holoviews/core/element.py:74: SyntaxWarning: "is" with a literal. Did you mean "=="?
  if key is ():
/srv/conda/envs/notebook/lib/python3.8/site-packages/holoviews/core/layout.py:225: SyntaxWarning: "is" with a literal. Did you mean "=="?
  if key is ():
/srv/conda/envs/notebook/lib/python3.8/site-packages/holoviews/element/tabular.py:60: SyntaxWarning: "is" with a literal. Did you mean "=="?
  if heading is ():

[philippjfr]

Thanks @rsignell-usgs, we'll fix those up asap.