LooseVersion is deprecated, use packaging.version instead

[hoxbro]

I'm getting a DeprecationWarning when this line is run.

plotly.py/packages/python/plotly/plotly/graph_objs/__init__.py

Line 272 in 00c18fd

if _LooseVersion(_ipywidgets.__version__) >= _LooseVersion("7.0.0"):

DeprecationWarning: distutils Version classes are deprecated. Use packaging.version instead.