当python substring命令的起始值为负时会发生什么?

use*_*129 -5 python

例:

mystring = " ... some string ... "
mystring[-50:40]  # <--- what does this mean?
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Ign*_*ams 7

切片中的负索引从右侧开始计数.是的,即使是起始值.

>>> '12345'[-4:4]
'234'
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