len() as upper boundary makes code less readable
Python tries to make the task of slicing lists and numpy.arrays as convenient as possible.
If one needs a slice which reaches till the end of the object the upper boundary can be left empty.
When negative numbers are used the indexing will start at the end.
Why you should care
Business Impacts
It is recommended to avoid these in order to ensure the code is more readable and cost effective.
CAST recommendations
References
Quantified code :
https://www.quantifiedcode.com/knowledge-base/readability/Omit%20%60len%28%29%60%20as%20upper%20boundary/27a0ZNa7
https://www.quantifiedcode.com/knowledge-base/Omit%20%60len()%60%20for%20indexing/slicing/49Cho3Zk
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