Need Optional parameter for Keypoint class as we have one for BoundingBox

In case, we want to track the Keypoint transformations and pickout the labels which we want to use, It would be useful if we add label parameter.

As of now, we can do something like the below code in BB's :
`ia.BoundingBox(
x

An extra null pointer check is not needed in functions like the following.

• LEdge
• [Range_tree_1](https://githu

Please add additional examples of how to deal with the data generated by events. Expand on an example of how to use data of creating a line, etc. I normally understand the 'e' but I am missing the relevant data generated in the event, where is it? How does someone take this utility to the next level? How do you find your data for storing in a database (not how to store it, but where is the data

It would be nice to have a shortcut for "Map It!" button to speed-up the experiments with WKT. Ctrl+enter and Shift+enter when the input is focused seem to be a reasonable choice for this!

Leaflet is listed as an external dependency in the rollup config, but it appears to still be bundled in the dist files.

Thanx a lot for you lib
Please can you give a small example of using it without node.js
We have "snake" track and we need to calculate interselections and show it.
is anyone hase the same task ?

find . -iname '*.py' | grep -vE 'example|docs' | xargs -P 4 -I{} python3.8 -Wall -m py_compile {}
./tests/test_pyclipper.py:276: SyntaxWarning: "is" with a literal. Did you mean "=="?
  self.assertTrue(len(node.Contour) is 0 or len(node.Contour) > 2)