Series.str.
index
Return lowest indexes in each string in Series/Index.
Each of the returned indexes corresponds to the position where the substring is fully contained between [start:end]. This is the same as str.find except instead of returning -1, it raises a ValueError when the substring is not found. Equivalent to standard str.index.
str.find
str.index
Substring being searched.
Left edge index.
Right edge index.
See also
rindex
Return highest indexes in each strings.